New polyhydroxyalkanoate copolymer, resin composition, molded product, toner, image forming method and image forming apparatus

ABSTRACT

A polyhydroxyalkanoate copolymer comprises one kind of unit of 
 
—[OCH((CH 2 ) x —SOC 6 H 5 R)CH 2 CO]— (n= 1 - 7 )   ( 1 ) 
 
(wherein R is any one of H, halogen, CN, NO 2 , COOR′, SO 2 R″ (R′ is any one of H, Na, K, CH 3  and C 2 H 5 ; R″ is any one of OH, ONa, OK, halogen, OCH 3  and OC 2 H 5 ), CH 3 , C 2 H 5 , C 3 H 7 , (CH 3 ) 2 —CH and (CH 3 ) 3 —C) and 
 
—[OCH((CH 2 ) x —SO 2 C 6 H 5 R)CH 2 CO]— (n= 1 - 7 )   ( 2 ) 
 
(wherein R is any one of H, halogen, CN, NO 2 , COO R′, SO 2 R″ (R′ is any one of H, Na, K, CH 3  and C 2 H 5 ; R″ is any one of OH, ONa, OK, halogen, OCH 3  and OC 2 H 5 ), CH 3 , C 2 H 5 , C 3 H 7 , (CH 3 ) 2 —CH and (CH 3 ) 3 —C) and at least one unit of chemical formulae ( 3 ) to ( 6 ): 
 
—[OCH((CH 2 ) m —Rz)CH 2 CO]— (n= 1 - 8 )   ( 3 ) 
(wherein Rz comprises a residue having either a phenyl structure or a thienyl structure), 
 
—[OCH((CH 2 ) k —C 6 H 11 Ra)CH 2 CO]— (n= 1 - 8 )   ( 4 ) 
 
(wherein R a  is any one of H, CN, NO 2 , halogen, CH 3 , C 2 H 5 , C 3 H 7 , CF 3 , C 2 F 5  and C 3 F 7 ) 
 
—[OCH((CH 2 ) n —CH═CH 2 )CH 2 CO]— (n= 1 - 8 )   ( 5 ), and 
 
—[OCH((CH 2 ) n —COORb)CH 2 CO]— (n= 1 - 8 )   ( 6 ) 
 
(wherein R b  is any one of H, Na and K).

TECHNICAL FIELD

The present invention relates to a polyhydroxyalkanoate copolymercomprising a new unit, a method for producing a precursor thereof usingmicroorganisms, and a method for producing the copolymer by oxidizationof the precursor. Moreover, the present invention relates to a resincomposition, a molded article obtained by using the same, and aproduction method thereof. Furthermore, the present invention relates toa binder resin that can be used for a toner for development of anelectrostatic latent image, which is used in recording methods such asthe electrophotography, electrostatic recording method, or magneticrecording method, a toner used for electrostatic latent imagedevelopment, an image forming method using the toner, and an imageforming apparatus using the toner.

BACKGROUND ART

Background Art of Resin

(Problems Regarding the Conventionally Used Resin)

Plastics such as a polyethylene terephthalate (PET) resin, polyesterresin, vinyl chloride resin or polyolefin resin have previously beenused for a wide range of uses as molded articles, e.g., containers suchas food containers, beverage bottles, cosmetic containers or plant pots.

The majority of these plastics are discarded after use. The plasticwastes have previously been disposed by incineration or landfilling.However, since the wastes generate a great burning energy byincineration, they have problems such as regarding the durability ofincinerators caused by a high burning temperature, processing cost byhigh temperature durable incinerators, and air pollution caused bygeneration of toxic combustion gas such as carbon monoxide, sulfurcompounds, chlorine gas or dioxin. In addition, when the plastic wastesare landfilled, they remain without being decomposed on a semi-permanentbasis, and they are accumulated as wastes in a disposal field, therebycausing a social problem that is called a waste problem. Moreover, sincethe plastic wastes exist as are in the earth, they cause a problemregarding instability of the ground in a landfill site, and there isalso a risk that the wastes might affect the natural environment andvarious types of organisms in the landfill site or the peripheral area.

Thus, to solve these problems, a biodegradable resin has become a focusof attention in these years. The term “biodegradable resin” is usedherein to mean a resin, which has physical properties almost equivalentto those of general-purpose plastics during the use as a material, butafter the use, is rapidly decomposed by microorganisms in the naturalenvironment such as on the earth, in the earth, in the compost, in theactive slurry, or in the water. The resin is decomposed into a fineform, and several types of biodegradable resins are finally convertedinto carbon dioxide and water.

Other than specific polyester biodegradable resins, blended resincompositions have conventionally been known to satisfy the abovedescribed requirements, and examples of such blended resin compositionsinclude a starch-ethylene vinyl alcohol copolymer resin, an ethylenevinyl alcohol copolymer resin-aliphatic polyester resin, and analiphatic polyester resin-polyolefin resin. These resins or resincompositions are molded into various forms such as a bottle and are inpractical use. However, a resin composition, which is excellent inmoldability required in its production process, as well as variousphysical properties required as containers and biodegradability requiredafter being discarded, has not yet been proposed. For example, a resincomposition having both biodegradability and heat resistance in amolding process has not yet been accomplished.

(Concerning polyhydroxyalkanoate (PHA))

By the way, in recent years, as a method for solving the problemregarding environmental contamination caused by wastes such as plasticmolded articles, the use of a biodegradable resin synthesized bymicroorganisms as a molding material has been proposed. Examples ofknown biodegradable resins derived from microorganisms includepolyhydroxyalkanoate (hereinafter referred to as PHA at times) such as acopolymer (hereinafter referred to as PHB/V) of poly-3-hydroxy-n-butyricacid (hereinafter referred to as PHB at times) or 3-hydroxy-n-butyricacid (hereinafter referred to as 3HB at times) and 3-hydroxy-n-valericacid (hereinafter referred to as 3HV at times), polysaccharide such asbacteria cellulose or Pullulan, and polyamino acid such aspoly-γ-glutamic acid or polylysine. In particular, PHA is, as with theconventional plastics, used for various products after undergoing amelt-processing. Further, since PHA is excellent in biodegradability, itis expected that this compound will be applied to soft components formedical use, etc.

It has hitherto been reported that many microorganisms producepoly-3-hydroxybutyric acid (PHB) or other PHAs and accumulate it in thecell. Like conventional plastics, these polymers can be utilized for theproduction of various products by melt processing or the like. Also,since they are biodegradable, they have an advantage of being completelybroken down by microorganisms in the natural world, and by no meansremain in natural environment to cause pollution unlike manyconventional synthetic polymeric compounds.

It is known that such PHAs produced by microorganisms may have variouscompositions and structures depending on types of microorganisms usedfor its production, the composition of culture medium, the conditionsfor culture and so forth. Researches on how to control such compositionsand structures have hitherto chiefly been made from the viewpoint of theimprovement in physical properties of PHAs.

(1) Especially, biosynthesis of PHA obtained by polymerization of amonomer units with a relatively simple structure such as 3HB, 3HV,3-hydroxyhexanoic acid (hereinafter referred to as 3HHx) and4-hyddroxy-n-butyric acid (hereinafter referred to as 4HB) have beenstudied, and production using various microorganisms has been reported(Japanese Patent Publications Nos. 6-15604, 7-14352 and 8-19227;Japanese Patent Application Laid-Open Nos. 5-7492, 5-93049, 7-265065 and9-191893; Japanese Patent No. 2642937 and Appl. Environ. Microbiol.,58(2), 746, 1992).

(2) When, however, broader application of such PHAs produced bymicroorganisms, e.g., application as functional polymers is taken intoaccount, a PHA in which a substituent other than an alkyl group has beenintroduced in the side chain, i.e., “unusual PHA” is expected to be veryuseful. Examples of such a substituent may include those containingaromatic rings (such as a phenyl group and a phenoxy group), andunsaturated hydrocarbons, an ester group, an allyl group, a cyano group,halogenated hydrocarbons and epoxides.

For example, there are reports on production of: PHA containing a phenylgroup or its partially substituted group such as PHA containing3-hydroxy-5-phenylvaleric acid as a unit using 5-phenylvaleric acid as asubstrate (Makromol. Chem. Phys., 191, 1957-1965 (1990); Macromolecules,24, 5256-5260 (1991) and Chirality, 3, 492-494 (1991)), PHA containing3-hydroxy-5-(4′-tolyl) valeric acid as a unit using 5-(4′-tolyl) valericacid as a substrate (Macromolecules, 29, 1762-1766 (1996)), and PHAcontaining 3-hydroxy-5-(2′, 4′-dinitrophenyl) valeric acid and3-hydroxy-5-(4′-nitrophenyl) valeric acid as a unit using 5-(2′,4′-dinitrophenyl) valeric acid as a substrate (Macromolecules, 32,2889-2895 (1999)); PHA containing a phenoxy group or its partiallysubstituted group such as PHA copolymer containing3-hydroxy-5-phenoxyvaleric acid and 3-hydroxy-9-phenoxynonanoic acidusing 11-pheoxyundecanoic acid as a substrate (Macromol. Chem. Phys.,195, 1665-1672 (1994)), PHA containing a 3-hydroxy-4-phenoxybutyric acidunit and a 3-hydroxy-6-phenoxyhexanoic acid unit from 6-phenoxyhexanoicacid, PHA containing a 3-hydroxy-4-phenoxybutyric acid unit, a3-hydroxy-6-phenoxyhexanoic acid unit, and a 3-hydroxy-8-phenoxyoctanoicacid unit from 8-phenoxyoctanoic acid, and PHA containing a3-hydroxy-5-phenoxyvaleric acid unit and a 3-hydroxy-7-phenoxyheptanoicacid unit from 11-phenoxyundecanoic acid (Macromolecules, 29, 3432-3435(1996)). There is also a report (Japanese Patent No. 2989175) on ahomopolymer consisting of 3-hydroxy-5-(monofluorophenoxy) pentanoate(3H5(MFP)P) units or 3-hydroxy-5-(difluorophenoxy) pentanoate(3H5(DFP)P) units, and a PHA copolymer containing at least (3H5(MFP)P)units or (3H5(DFP)P) units, of which advantage is to providestereoregularity and water repellency while maintaining a high meltingpoint and good processability.

Further, studies are conducted on cyano-substituents andnitro-substituents in addition to the fluorine-substituent describedabove. For example, PHA containing 3-hydroxy-p-cyanophenoxyhexanoic acidor 3-hydroxy-p-nitrophenoxyhexanoic acid as a monomer unit is producedusing octanoic acid and p-cyanophenoxyhexanoic acid orp-nitrophenoxyhexanoic acid as substrates (Can. J. Microbiol., 41, 32-43(1995); and Polymer International, 39, 205-213 (1996)).

These reports are useful in obtaining polymers each having an aromaticring in the side chain of PHA and having properties derived therefromunlike general PHA whose side chain contains an alkyl group. Further, asthe example of unusual-PHA having a cyclohexyl group, production of PHAfrom cyclohexylbutyric acid or cyclohexylvaleric acid has been reported(Macromolecules, 30, 1611-1615 (1997)).

(3) Without being confined merely to changes in physical properties,research in a new category is being conducted to produce a PHA having asuitable functional group in the side chain.

For example, a study has been made to produce a PHA having, in a unitthereof, an active group having high reactivity in an addition reaction,such as a bromo group or vinyl group, and to introduce any givenfunctional group into the side chain of the polymer by chemicaltransformation using the above active group, so as to obtain amultifunctional PHA.

As an example of synthesizing a PHA containing a unit having a thioether(—S—; a sulfanyl linkage), which is expected to provide a highreactivity, Macromolecules, 32, 8315-8318 (1999) reports thatPseudomonas putida strain 27N01 produces a PHA copolymer of3-hydroxy-5-thiophenoxyvaleric acid (3-hydroxy-5-(phenylsulfanyl)valericacid) with 3-hydroxy-7-thiophenoxyheptanoic acid(3-hydroxy-7-(phenylsulfanyl)heptanoic acid), using11-thiophenoxyundecanoic acid (11-(phenylsulfanyl)undecanoic acid) as asubstrate.

Macromol. Rapid Commun., 20, 91-94 (1999) has reported that usingPseudomonas oleovorans, a PHA having a bromo group on a side chainthereof is produced, and then the side chain is modified with the thiolproduct of an acetylated maltose, so as to synthesize PHAs havingdifferent solubility and hydrophilicity.

It is reported in Polymer, 41, 1703-1709 (2000) that a change ofsolubility in solvents has been found such that 3-hydroxyalkanoic acidhaving diol on the side chain terminal, synthesized by an oxidationreaction using potassium permanganate after producing PHA containing asa monomer unit 3-hydroxyalkenoic acid having an unsaturated bond in theterminal of the side chain terminal using 10-undecenoic acid as asubstrate, is rendered soluble in polar solvents such as methanol,acetone-water mixture (80/20, v/v) and dimethylsulfoxide, and insolublein nonpolar solvents such as chloroform, tetrahydrofuran and acetone.

Likewise, Macromolecules, 31, 1480-1486 (1998) has reported that usingPseudomonas oleovorans, polyester having a vinyl group on a side chainthereof is produced, and then the vinyl group is epoxidized, so as toproduce polyester having an epoxy group on a side chain thereof.

Moreover, Polymer, 35, 2090-2097 (1994) has reported that using a vinylgroup on the side chain of polyester, a crosslinking reaction is carriedout in the polyester molecule, so as to improve the properties of thepolyester.

It is reported in Macromolecular chemistry, 4, 289-293 (2001) that animprovement in speed of decomposition has been found for PHA containing3-hydroxy-10-carboxydecanoic acid as a monomer unit, synthesized by anoxidization cleavage reaction using potassium permanganate afterproducing PHA containing as a monomer unit 3-hydroxy-10-undecenoic acidusing 10-undecenoic acid as a substrate.

At the same time, in order to change the physical properties of a PHAhaving an active group in its unit and to actually use it as a polymer,the synthesis of a PHA copolymer comprising units other than unitshaving active groups by using microorganisms has been studied.Macromolecules, 25, 1852-1857 (1992) has reported that using Pseudomonasoleovorans, a PHA copolymer comprising a 3-hydroxy-ω-bromoalkanoic acidunit and a straight-chain alkanoic acid unit has been produced in thecoexistence of ω-bromoalkanoic acid and n-nonanoic acid, such as11-bromoundecanoic acid, 8-bromooctanoic acid and 6-bromohexanoic acid.

Thus, into a PHA having, in its units, active groups with highreactivity, such as a bromo or vinyl group, various functional groupscan be introduced. Or, chemical transformation can also be performed onsuch a PHA. Moreover, since a PHA having an active group can be acrosslink point of a polymer, it can be said that such a PHA isextremely effective to achieve multifunctionality of a PHA.

BACKGROUND ART OF TONER

A large number of electrophotographic methods have been known so far. Ingeneral, copied images are obtained by forming an electrostatic latentimage on an image-bearing member (photosensitive member) by utilizing aphotoconductive material and by various means, subsequently developingthe latent image by the use of a toner to form a visible image (tonerimage), transferring the toner image to a transfer medium as theoccasion demands, then fixing the toner image to the transfer medium byheating and/or pressing. As methods by which the electrostatic latentimage is formed into a visible image, cascade development, magneticbrush development, pressure development and so forth are known in theart. Another method is also known in which, using a magnetic toner and arotary developing sleeve provided with magnetic poles at the core, themagnetic toner is caused to fly from the developing sleeve to thephotosensitive member by the aid of an electric field.

As development methods used when electrostatic latent images aredeveloped, available are a two-component development method making useof a two-component type developer comprised of a toner and a carrier anda one-component development method making use of a one-componentdeveloper using no carrier and comprised of only a toner.

Fine colored particles commonly called a toner are composed of a binderresin and a colorant as essential components and optionally a magneticmaterial and so forth.

(Concerning Binder Resin)

Binder resin is made up of a major part of toner. Accordingly, thephysical properties of a binder resin have a great effect on thephysical properties of the toner. For example, a binder resin isrequired to have delicate hardness and hot-melt properties. Tonerobtained by crushing and classifying a binder resin containing adispersed coloring agent or the like is required to show goodflowability, without generating fine particles by mechanical impulsegenerated as a result of stirring in a development apparatus or withoutaggregation of the toner itself. Moreover, it is required that a toneris quickly melted at a low temperature when it is fixed, and that themelted toner shows cohesiveness when it is melted. This is to say, it ispossible to control the physical properties of a toner by controllingthe physical properties of a binder resin.

As binder resins, a styrene-acrylic ester copolymer, a polyester resin,an epoxy resin, an olefin resin and others have conventionally beenused. Of these, a polyester resin is now widely used as a resin forheat-roll fixing for the reasons that when it is melted, the dispersionof toner additives such as carbon black or wetting into a transfer paperprogresses favorably, and that it is also excellent in fixability.

Moreover, from the viewpoint of environmental protection, recently,people worldwide are more aware of the recycling of source, thereduction of wastes and the improvement of safety of wastes than ever.The above objects should be achieved also in the field ofelectrophotography. That is, with the diffusion of copying machines andprinters, the wasted amount of a toner fixed on a paper, a used wastetoner, and printed papers has increased year by year. Since theconstitutional components of the conventional toner are all stableartificial compounds, the conventional toner is persistent, and in somecases, it remains for a long time in any type of the environment such asin the earth or in the water. Furthermore, recycling and reusing ofordinary papers is an important object for recycling source. However,when the conventional binder resins including a styrene resin as atypical example are used for a toner, it is difficult to deink it byalkali hydrolysis, and therefore, this is one of the objects forrecycling ordinary papers. Still further, from the viewpoint ofprotection of terrestrial environment and influence on the human body,safety of wastes is also an important object.

(Application of Biodegradable Resin to Toner)

In the field of electrophotography also, a method of using abiodegradable resin as a binder resin has been proposed to achieve atoner causing no environmental contamination when it is discarded.

Japanese Patent Application Laid-Open No. 6-289644 disclose anelectrophotographic toner particularly used for heat-roll fixing, whichis characterized in that at least a binder resin contains a vegetablewax and a biodegradable resin (as exemplified by polyesters produced bymicroorganisms and natural polymeric materials derived from vegetablesor animals), and the vegetable wax is added to the binder resin in anamount of from 5 to 50% by weight.

Japanese Patent Application Laid-Open No. 8-262796 discloses anelectrophotographic toner containing a binder resin and a colorant, andis characterized in that the binder resin comprises a biodegradableresin (as exemplified by aliphatic polyester resins) and the colorantcomprises a water-insoluble coloring matter.

Moreover, U.S. Pat. No. 5,004,664 discloses a toner comprising, as acomposition, a biodegradable resin, especially, polyhydroxybutyric acid,polyhydroxyvaleric acid, a copolymer thereof, or a blended form thereof.

In these techniques, binder resins have problems regarding theiressential functions. For example, since binder resins are biodegradable,when a toner containing such resins is landfilled, it is certainlydecomposed in the earth, but it has low durability. Moreover, highhygroscopicity of these binder resins results in unstable electricalcharge. For example, PHB is a hard brittle material with properties suchas a melting point of 180° C., a degree of crystallinity between 50% and70%, a Young's modulus of 3.5 Gpa, and a breaking extension of 5%, andso it is unsatisfactory to be practically used as a binder resin for atoner.

Toner comprising polylactic acid aliphatic polyester as a main componenthas been disclosed for the reason that the toner has biodegradabilityand is efficiently decomposed by alkali hydrolysis so that it is usefulfor recycling of papers. For example, Japanese Patent ApplicationLaid-Open No. 7-120975 has proposed a method for preparing a toner froma lactic acid homopolymer, and polylactic acid obtained by ring-openingpolymerization has been described therein as a typical example.

In the ring-opening polymerization, lactic acid is once oligomerized bydehydration, the oligomerized product is then converted into a cyclicdimer lactide by depolymerization, and it is then subjected toring-opening polymerization. Since this method comprises suchcomplicated steps, the obtained polylactic acid used as a resin for atoner is extremely expensive.

Moreover, since the above ring-opening polymerization is a cationicring-opening polymerization, used solvents should be anhydrouscompounds, and ionic species as a polymerization terminator should beremoved. Thus, since this method has low production efficiency andmonomer species used in the production of polyester is limited to acyclic ester, it is difficult to control physical properties necessaryas a resin for a toner. Furthermore, it is also difficult tocopolymerize with various monomers to control the balance betweendegradability and physical properties. Accordingly, a low-costdegradable polyester whose physical properties are easily controlled isdesired. When a toner is directly produced from polylactic acid, theobtained toner has problems regarding preservative quality andanti-offset property. Accordingly, it has not yet been in actual use.

Japanese Patent Application Laid-Open No. 9-274335 discloses anelectrostatic latent image developing toner characterized in that itcontains a polyester resin obtained by dehydrating polycondensation of acomposition containing lactic acid and tri- or higher functionaloxycarboxylic acid and a coloring agent. However, since the polyesterresin is formed through dehydrating polycondensation of an alcohol groupin lactic acid and a carboxylic acid group in oxycarboxylic acid, themolecular weight of the obtained resin is likely to increase, and it istherefore considered that biodegradability is lowered. Moreover, as withJapanese Patent Application Laid-Open No. 7-120975, this resin causesproblems regarding the preservative quality and anti-offset property ofthe obtained toner.

Japanese Patent Application Laid-Open No. 9-281746 still also disclosesa toner for developing electrostatic latent images which ischaracterized by containing a urethanated polyester resin and acolorant; the urethanated polyester resin being obtained bycross-linking polylactic acid with a tri- or more functional polybasicisocyanate.

However, this toner also has problems regarding degree ofbiodegradability, preservative quality and anti-offset property.

Moreover, polycaprolactone that is a representative homopolymer ofhydroxycarboxylic acid has a low melting point and a low glasstransition point, and is excellent in compatibility with various typesof resins. However, since it has a low melting point of 60° C., it isnot suitable as a binder resin when it is used singly. Furthermore,polylactic acid has a high glass transition point (60° C.), andcrystalline polylactic acid is a thermoplastic polymer having a highmelting point (around 180° C.). However, as stated above, it has not yetpractically used as a binder resin. Still further, a toner resinconsisting of the conventional degradable polyester generally has poorcrushability, and therefore it is difficult to use such a toner resin asa binder resin, which makes up 90% of a toner with a particle size ofapproximately 10 μm. Thus, when considered the commercialization of theabove toner resin as a binder resin, the improvement of its physicalproperties is strongly desired.

In all the electrophotographic toners stated above, biodegradable resinsare used as their binder resins, and they are understood to have theeffect of contributing to environmental conservation.

(Concerning Other Prior Art Publications)

In the invention of the present application, microorganisms described inJapanese Patent Applications Laid-Open Nos. 2001-288256 and 2002-80571are used. Description regarding a medium in Non Patent Publication 17can be incorporated herein by reference. Moreover, J. Chem. Soc.,Perkin. Trans. 1, 806 (1973), Org. Synth., 4, 698 (1963), J. Org. Chem.,46, 19 (1981), and J. Am. Chem. Soc., 81, 4273 (1959) describe thatcarboxylic acid is obtained by cleaving the double bond of carbon-carbonby oxidation with an oxidizing agent.

That is to say, both the conventional plastic molded articles and tonerbinders for electrophotographic toner comprise, as raw materials, aresin that is not decomposed in the nature and thereby might causevarious environmental problems, when it is directly discarded. The usedamount of such a resin is increasing year by year. Accordingly, it isstrongly desired to take measures against waste treatment quickly.

The previously reported polyester that is obtained by chemical reactionand treatment of polyester having a vinyl group can possess variousfunctions, but since it has a medium or long alkyl chain on a side chainthereof, its thermal property is not necessarily preferable. That is tosay, the above polyester has a low glass transition temperature and alow melting point, thereby narrowing the applicable range as a moldedarticle or film.

On the other hand, as stated above, polyester having an aromatic ring ona side chain thereof generally has a character that it has a highmelting point and also has a wide applicable range as a molded articleor film. However, in general, the above described “unusual PHA” also hasa low glass transition temperature (up to approximately 30° C.), and thecontrol of the solubility in a solvent has a certain limit. Accordingly,when various types of application and use of the PHA are considered, theimprovement of the thermal property (especially grass transitiontemperature) and the control of the solubility in a solvent are largeproblems.

Moreover, in the case of the above reported PHA in which a monomer unithaving a carbonyl group, epoxy group or diol group on a side chainterminal is introduced, the copolymer unit is a monomer unit having astraight-chain alkyl group on a side chain thereof, and this polymer hasa low glass transition temperature. Further, it is difficult to controlthe solubility in a solvent only by the monomer unit having thestraight-chain alkyl group.

For the above reasons, it is desired to achieve a PHA in which the ratioof a monomer unit can be arbitrarily controlled and its physicalproperties, especially its thermal property and solubility in a solventcan be arbitrarily controlled, so that the application as a polymer isnot limited, and a method for producing the same.

DISCLOSURE OF THE INVENTION

In order to solve the above described problems, the present invention isprovided to achieve a polyhydroxyalkanoate-type polyester copolymerhaving a unit comprising a phenylsulfinyl and/or phenylsulfonyl groupthat is available for various types of application, and a method forproducing the same.

Moreover, the present invention is also provided to achieve a resincomposition comprising the above polyhydroxyalkanoate-type polyester ora copolymer thereof, which can prevent various environmental problemscaused by wastes, a molded article obtained by using the resincomposition, and a method for producing the same. Furthermore, thepresent invention is also provided to achieve a molded articleconsisting of a biodegradable resin excellent in extrusion moldingproperty, mechanical property, heat resistance and other properties, andespecially a resin composition having both biodegradability and heatresistance when it is molded.

Still further, as stated above, by applying biological engineering meansto the production of a resin composition and a molded article, itbecomes possible to produce a novel resin composition and a novel moldedarticle, which have been hardly produced by the conventional organicsynthetic chemical method. Still further, in the conventional organicsynthetic chemical method, the production process consists of multisteps of reactions, but in the present invention, the production processconsists of only one step in many cases. Accordingly, the simplificationof a production process, cost-reduction, the reduction of time requiredare also expected. Still further, the present invention also enables thereduction of use of organic solvents, acid, alkali, surfactants andothers, the setting of moderate reaction conditions, and synthesis fromnonoil materials or raw materials with low purity, thereby realizing anenvironmentally low burden and source recycling-type synthetic process.

Describing the above synthesis from raw materials with low purityfurther in detail, since the substrate specificity of enzyme as acatalyst is generally high in a biological engineering syntheticprocess, although low-purity raw materials are used, it is possible toadvance a desired reaction, selectively. Accordingly, this syntheticprocess can also be expected to be sued for wastes or recyclingmaterials.

What is more, the present invention is provided to achieve: a binderresin comprising the above polyhydroxyalkanoate-type polyester or acopolymer thereof, which is biodegradable, highly contributes to theprotection of the natural environment, facilitates the conventionaldeinking process of using alkali, so as to promote the reuse of usedcopying papers, and also satisfies various properties as a tonerincluding carrier spent, fogging, stability in electrification,durability, stability in conservation, crushability, cost, etc.; anelectrostatic latent image developing toner comprising the above binderresin; and an image forming method and an image forming apparatus usingthe toner.

According to an aspect of the-present invention, there is provided apolyhydroxyalkanoate copolymer comprising at least, per polymermolecule, one kind of unit selected from the group consisting ofchemical formulae (1) and (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅) , CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COO R′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and at least one unit selected from the group consisting ofchemical formulae (3) to (6):

(wherein m is an integer selected from the range shown in the samechemical formula; Rz comprises a residue having either a phenylstructure or a thienyl structure; and when more than one unit exist, mand Rz of each unit can independently represent any one of the integersand the substituents described above, respectively)

(wherein R_(a) is any one selected from the group consisting of H, CN,NO₂, halogen, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇; k is an integerselected from the range shown in the same chemical formula; and whenmore than one unit exist, k and R_(a) of each unit can independentlyrepresent any one of the integers and the substituents described above,respectively)

(wherein n is an integer selected from the range shown in the samechemical formula, and when more than one unit exist, n of each unit canrepresent any one of the integers described above independently)

(wherein n is an integer selected from the range shown in the samechemical formula; R_(b) is any one selected from the group consisting ofH, Na and K; and when more than one unit exist, n and R_(b) of each unitcan independently represent any one of the integers and the substituentsdescribed above, respectively).

According to another aspect of the present invention, there is provideda process of preparing a polyhydroxyalkanoate copolymer comprising, perpolymer molecule, a 3-hydroxy-(substituted phenylsulfanyl)alkanoic acidunit having chemical formula (7):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and at least one unit selected from the group consisting ofunits having chemical formulae (4), (5) and (20):

(wherein m is an integer selected from the range shown in the samechemical formula; Rx comprises a residue having either a phenylstructure or a thienyl structure; and when more than one unit exists, mand Rx of each unit can independently represent any one of the integersand the substituents described above, respectively), which comprises thesteps of allowing a microorganism capable of producing thepolyhydroxyalkanoate copolymer to biosynthesize the polyhydroxyalkanoatecopolymer under the condition that at least one ω-(substitutedphenylsulfanyl)alkanoic acid having chemical formula (16):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅) , CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and s is an integer selected from 1 to 7 and can differfor each unit) and at least one compound selected from the groupconsisting of compounds having chemical formulae (17), (18) and (19):

(wherein q is an integer selected from the range shown in the samechemical formula; and Rx comprises a residue having either a phenylstructure or a thienyl structure)

(wherein R_(a) is any one selected from the group consisting of H, CN,NO₂, halogen, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇; r is an integerselected from the range shown in the same chemical formula)

(wherein p is an integer selected from the range shown in the samechemical formula) exist.

According to still another aspect of the present invention, there isprovided a process of preparing a polyhydroxyalkanoate copolymercomprising, per polymer molecule, at least one unit selected from thegroup consisting of formulae (1) and (2) and at least one unit selectedfrom the group consisting of chemical formulae (3) to (6), whichcomprises the steps of employing as a raw material apolyhydroxyalkanoate copolymer comprising, per polymer molecule, a3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit having chemicalformula (7) and at least one unit selected from the group consisting ofchemical formulae (4), (5) and (20) and oxidizing at a time the3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit having chemicalformula (7) and the at least one unit selected from the group consistingof chemical formulae (4), (5) and (20).

According to a further aspect of the present invention, there isprovided a resin composition comprising a resin (A) that is comprised ofa polyhydroxyalkanoate comprising, per polymer molecule, at least oneunit selected from the group consisting of 3-hydroxy-(substitutedphenylsulfinyl)alkanoic acid units having chemical formula (1) and3-hydroxy-(substituted phenylsulfonyl)alkanoic acid units havingchemical formula (2) and a thermoplastic resin (B) that comprises nounit selected from the group consisting of 3-hydroxy-(substitutedphenylsulfinyl)alkanoic acid units having chemical formula (1) and3-hydroxy-(substituted phenylsulfonyl)alkanoic acid units havingchemical formula (2), the content of the resin (A) being higher thanthat of the resin (B) in terms of mass percentage.

According to a further aspect of-the present invention, there isprovided a resin composition comprising the resin (A) and an additivefor resin.

According to a further aspect of the present invention, there isprovided a resin for being decomposed by microorganisms comprising theresin (A).

According to a further aspect of the present invention, there isprovided a method of decomposing the resin (A) comprising the steps ofproviding the resin and decomposing the resin in contact withmicroorganisms.

According to a further aspect of the present invention, there isprovided a binder resin for forming a resin-based powder or granularmaterial, which comprises a polyhydroxyalkanoate comprising, per polymermolecule, at least one unit selected from the group consisting of3-hydroxy-(substituted phenylsulfinyl)alkanoic acid units havingchemical formula (1) and 3-hydroxy-(substituted phenylsulfonyl)alkanoicacid units having chemical formula (2).

According to a further aspect of the present invention, there isprovided a toner for developing electrostatic charge images, wherein thetoner comprises the binder resin according to the binder resin of thepresent invention.

According to a further aspect of the present invention, there isprovided a method for forming an image comprising the steps of chargingan electrostatic latent image carrier by applying voltage to a chargingmember from outside; forming an electrostatic charge image on thecharged electrostatic latent image carrier; developing the electrostaticcharge image with a toner for developing electrostatic charge images toform a toner image on the electrostatic latent image carrier;transferring the toner image on the electrostatic latent image carrierto a recording medium; and fixing the toner image on the recordingmedium by heat, wherein the toner for developing electrostatic chargeimages of the present invention is used.

According to a further aspect of the present invention, there isprovided an image forming apparatus comprising a charging means ofcharging an electrostatic latent image carrier by applying voltage to acharging member from outside; an electrostatic charge image formingmeans for the step of forming an electrostatic charge image on thecharged electrostatic latent image carrier; a developing means ofdeveloping the electrostatic charge image with a toner for developingelectrostatic charge images to form a toner image on the electrostaticlatent image carrier; a transferring means of transferring the tonerimage on the electrostatic latent image carrier to a recording medium;and a fixing means of fixing the toner image on the recording medium byheat, wherein the toner for developing electrostatic charge images ofthe present invention is used.

According to the present invention, there are provided apolyhydroxyalkanoate copolymer comprising a monomer unit having aphenylsulfinyl or phenylsulfonyl structure on a side chain terminalthereof and further comprising a monomer unit having a substituent groupother than a straight-chain alkyl group, such as a phenyl structure,thienyl structure or cyclohexyl structure, a vinyl group, or a carbonylgroup on a side chain thereof; and a method for producing the same. Thepresent invention enables the improvement of the thermal property of apolyhydroxyalkanoate copolymer and the control of the solubility in asolvent, thereby contributing greatly to the industry.

Moreover, according to the present invention, there are provided a resincomposition, which comprises a polyhydroxyalkanoate having at least onetype of unit selected from a group consisting of3-hydroxy-(phenylsulfinyl)alkanoic acid units and3-hydroxy-(phenylsulfonyl)alkanoic acid units and has biodegradability,heat resistance and mechanical property in a well balanced manner; amolded article; and a method for producing the same.

The resin composition of the present invention can be used for varioustypes of heating apparatuses, containers, automotive parts, etc., andmore specifically, it can be used for containers such as foodcontainers, beverage containers, toiletry containers includingcontainers for shampoo or conditioner, drug containers, cosmeticcontainers, etc.

Furthermore, according to the present invention, there are provided abinder resin comprising a PHA having at least one type of unit selectedform a group consisting of 3-hydroxy-(phenylsulfinyl)alkanoic acid unitsand 3-hydroxy-(phenylsulfonyl)alkanoic acid units, which isbiodegradable, highly contributes to the protection of the naturalenvironment, facilitates the conventional deinking process of usingalkali, so as to promote the reuse of used copying papers, and alsosatisfies various properties as toner including carrier spent, fogging,stability in electrification, durability, stability in conservation,crushability, cost, etc.; an electrostatic latent image developing tonercomprising the binder resin; and an image forming method and an imageforming apparatus using the toner.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic explanatory view of an image forming apparatusused in Examples D-19 to D-34 and Comparative Examples D-3 and D-4;

FIG. 2 is a sectional view of a principal part of a developmentapparatus for a two-component developer used in Examples D-19 to D-34and Comparative Examples D-3 and D-4;

FIG. 3 is a schematic explanatory view of an image forming apparatushaving a reuse mechanism of a toner used in Examples D-35 to D-42 andComparative Examples D-5 and D-6;

FIG. 4 is a sectional view of a principal part of a developmentapparatus for a one-component developer used in Examples D-35 to D-42and Comparative Examples D-5 and D-6;

FIG. 5 is an exploded perspective view of a principal part of a fixationapparatus used in the Examples of the present invention;

FIG. 6 is an enlarged sectional view of a principal part showing a filmstate of the fixation apparatus used in the Examples of the presentinvention at the time when it is not driven; and

FIG. 7 is a schematic view showing a blow-off charge level measuringapparatus for measuring the charge level of the toner.

FIG. 8 shows a ¹H-NMR spectrum of the compound prepared in Preparationexample A-1;

FIG. 9 shows a ¹H-NMR spectrum of the compound prepared in Preparationexample A-1;

FIG. 10 shows a ¹H-NMR spectrum of the compound prepared in Preparationexample A-2;

FIG. 11 shows a ¹H-NMR spectrum of the compound prepared in Preparationexample A-2;

FIG. 12 shows a ¹H-NMR spectrum of the compound prepared in Preparationexample A-4;

FIG. 13 shows a ¹H-NMR spectrum of the compound prepared in Preparationexample A-4;

FIG. 14 shows a ¹H-NMR spectrum of the compound prepared in example A-1;

FIG. 15 shows a ¹H-NMR spectrum of the compound prepared in example A-2;

FIG. 16 shows a ¹H-NMR spectrum of the compound prepared in example A-3;

FIG. 17 shows a ¹H-NMR spectrum of the compound prepared in example A-4;

FIG. 18 shows a ¹H-NMR spectrum of the compound prepared in example A-5;

FIG. 19 shows a ¹H-NMR spectrum of the compound prepared in example A-6;

FIG. 20 shows a ¹H-NMR spectrum of the compound prepared in example A-7;and

FIG. 21 shows a ¹H-NMR spectrum of the compound prepared in example A-8.

BEST MODE FOR CARRYING OUT THE INVENTION

The polyhydroxyalkanoate copolymer of the present invention may furthercomprises, per polymer molecule, at least one unit selected from thegroup consisting of 3-hydroxy-(substituted phenylsulfanyl)alkanoic acidunits having chemical formula (7):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COO R′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit).

In the polyhydroxyalkanoate copolymer of the present invention, Rz inchemical formula (3) is preferably any one residue selected from thegroup consisting of chemical formulae (8), (9), (10), (11), (12), (13),(14) and (15):

(wherein R₁ is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′ except the substituent introduced into the para-positionof the phenyl group (R′ is any one selected from the group consisting ofH, Na and K) , CH₃, C₂H₅, C₃H₇, CH═CH₂, CF₃, C₂F₅ and C₃F₇, and whenmore than one unit exist, R₁ of each unit can represent any one of thesubstituents described above independently)

(wherein R₂ is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, SCH₃, CF₃, C₂F₅ and C₃F₇, and when more thanone unit exist, R₁ of each unit can represent any one of thesubstituents described above independently)

(wherein R₃ is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇, and when more than oneunit exist, R₃ of each unit can represent any one of the substituentsdescribed above independently)

(wherein R₅ is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R₅ of eachunit can represent any one of the substituents described aboveindependently)

, and when more than one unit exist, Rz of each unit can represent anyone of the residues described above independently.

The polyhydroxyalkanoate copolymer of the present invention preferablyhas a number average molecular weight of 1,000 to 1,000,000.

The above-mentioned condition in the process of preparing apolyhydroxyalkanoate copolymer of the present invention is preferablycomprised of cultivating the microorganism in a medium that comprises atleast one ω-(substituted phenylsulfanyl)alkanoic acid having chemicalformula (16) and at least one compound selected from the groupconsisting of compounds having chemical formulae (17) to (19). Themedium may further comprise at least one selected from the groupconsisting of peptides, yeast extract, organic acids or the saltsthereof, amino acids or salts thereof, saccharides, and strait-chainalkanoic acids with 4 to 12 carbon atoms or the salts thereof.Preferably, the petides are polypeptone; the organic acids or the saltsthereof are pyruvic acid, oxalacetic acid, citric acid, isocitric acid,ketoglutaric acid, succinic acid, fumaric acid, malic acid, lactic acidand the salts thereof; the amino acids or the salts thereof are glutamicacid, aspartic acid and the salts thereof; and the saccharides areglyceraldehyde, erythrose, arabinose, xylose, glucose, galactose,mannose, fructose, glycerol, erythritol, xylitol, gluconic acid,glucuronic acid, galacturonic acid, maltose, sucrose and lactose.Further, the process of preparing a polyhydroxyalkanoate copolymer maycomprise a step of recovering the polyhydroxyalkanoate copolymerproduced by the microorganism from the cells of the microorganism. Themicroorganism is preferably one classified as Pseudomonas sp., and morepreferably any one or more strains selected from the group consisting ofPseudomonas cichorii YN2 (FERM BP-7375), Pseudomonas cichorii H45 (FERMBP-7374) and Pseudomonas jessenii P161 (FERM BP-7376).

In the process of preparing a polyhydroxyalkanoate copolymer of thepresent invention, the polyhydroxyalkanoate copolymer as the rawmaterial is preferably prepared by any one process selected from thegroup consisting of the above-mentioned processes of the presentinvention. The oxidation is preferably conducted using one or moreoxidizing agents selected from the group consisting of permanganate,bichromate, periodate, hydrogen peroxide, sodium percarbonate,metachloroperbenzoate, performic acid and peracetic acid. The oxidizingagent is preferably permanganate and the oxidizing treatment isperformed under acidic conditions. Further, the oxidization ispreferably conducted using ozone.

In the process of preparing a polyhydroxyalkanoate copolymer of thepresent invention, Rz in chemical formula (3) is preferably at least anyone kind of residue selected from the group consisting of chemicalformulae (8), (9), (10), (11), (12), (13), (14) and (15), and Rx inchemical formula (20) is preferably-at least any one kind of residueselected from the group consisting of chemical formulae (9), (10), (11),(12), (13), (14), (15) and (21):

(wherein Rc is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, CH═CH₂, CF₃, C₂F₅ and C₃F₇ , and when morethan one unit exist, Rc of each unit can represent any one of thesubstituents described above independently).

In the resin composition of the present invention, the thermoplasticresin (B) is preferably comprised of one or more resins selected fromthe group consisting of polyester-based resin, polystyrene-based resin,polypropylene-based resin, polyethylene terephthalate-based resin,polyurethane-based resin, polyvinyl-based resin and polyamide-basedresin. The polystyrene-based resin is more preferably polystyrene. Thepolyester-based resin is more preferably poly-ε-caprolactone orpolylactic acid.

The resin composition of the present invention may further comprise anadditive for resin.

The binder resin of the present invention may further comprise athermoplastic resin other than the polyhydroxyalkanoate, wherein thecontent of the polyhydroxyalkanoate is higher than that of thethermoplastic resin in content by weight. The thermoplastic resin ispreferably one or more selected from the group consisting ofpolycaprolactone and polylactic acid.

In the binder resin of the present invention, the number averagemolecular weight of the binder resin is preferably 2,000 or more and300,000 or less.

The glass transition point of the binder resin of the present inventionis preferably 30 to 80° C. and the softening point of the same is 60 to170° C.

The resin-based powder or granular material in the binder resin of thepresent invention is preferably a toner for developing electrostaticcharge images.

The transferring step in the image forming method of the presentinvention preferably comprises a first transferring step of transferringthe toner image on the electrostatic latent image carrier to anintermediate transfer medium and a second transferring step oftransferring the toner image on the intermediate transfer medium to therecording medium.

The transferring means in the image forming apparatus of the presentinvention preferably comprises a first transferring means oftransferring the toner image on the electrostatic latent image carrierto an intermediate transfer medium and a second transferring means oftransferring the toner image on the intermediate transfer medium to therecording medium.

PHA

Polyhydroxyalkanoate used in the present invention has a basic skeletonas a biodegradable resin, and is therefore capable of being used forproducing various kinds of products through melt-processing and thelike, as in the case of conventional plastics, and it also has aremarkable characteristic such that it is decomposed by organisms andinvolved in the material cycle in the natural world, unlike syntheticpolymers derived from oil. Therefore, the compound requires nocombustion process, and it is an effective material in the sense that itcontributes to prevention of air pollution and global warming. Thecompound can be used as a plastic enabling preservation of environments.

Generally, Tm and Tg are important physical properties associated withthe heat resistance or mechanical strength (e.g., elastic modulus) ofresin materials. For example, a resin material with a high Tm or Tgvalue is excellent in heat resistance or strength. In contrast, a resinmaterial with a low Tm or Tg value is poor in heat resistance orstrength, although it has an advantage such as good moldability. Amajority of the conventional PHA has a relatively low Tm or Tg value.Therefore, their extrusion molding property, mechanical property andheat resistance have a certain limit, and the scale-up of the uses alsohas a certain limit.

In a case where the polyhydroxyalkanoate used in the present inventionis mixed with other resins to obtain a resin composition, when comparedwith the conventional resin composition using only the conventionalmcl-PHA or unusual-PHA, the obtained resin composition has improvedthermal property and improved mechanical property. Accordingly, the thusobtained resin composition can be applied to uses requiring the abovephysical properties. For example, it can be used under the environmentwhere the temperature is relatively high (140° C. or lower)

Moreover, as described later, the polyhydroxyalkanoate of the presentinvention can also be used as a raw material for a toner binder for anelectrophotographic toner. It has an extremely excellent character as abinder resin and can reduce burden on the environment caused by anelectrophotographic process. Furthermore, the polyhydroxyalkanoate ofthe present invention is highly safe to the human body or environment.Still further, when an electrostatic latent image developing tonercomprising the above binder resin is used in an image forming apparatushaving a certain development system, significant effects can beobtained.

The PHA having these desired physical properties can be obtained byselecting conditions for culturing microorganisms capable ofsynthesizing the PHA of the present invention, and other conditions. Forexample, the number average molecular weight of the PHA can becontrolled by controlling culture time or the like. Moreover, the numberaverage molecular weight can also be controlled by eliminating lowmolecular weight components by means such as solvent extraction orreprecipitation. Herein, a glass transition temperature and a softeningpoint correlate with the molecular weight of the PHA. It is alsopossible to control the glass transition temperature and the softeningpoint by controlling the type and/or composition ratio of monomer unitscomprised in the PHA.

The molecular weight of the PHA is desirably between 1,000 and10,000,000 at a number average molecular weight.

When such a compound is produced using microorganisms, the polyesterresin is an isotactic polymer consisting only of an R form. However, ifthe object of the present invention is achieved from both physical andfunctional-aspects, it is not necessarily an isotactic polymer, but anatactic polymer can also be used. Moreover, it is also possible toproduce the PHA by a chemical synthesis method in which a lactonecompound is subjected to ring-opening polymerization using an organicmetal catalyst (e.g., an organic catalyst containing aluminum, zinc ortin).

A PHA of interest in the present invention comprises at least one typeof unit selected from a group consisting of a 3-hydroxy-(substitutedphenylsulfinyl)alkanoic acid unit expressed by chemical formula (1) anda 3-hydroxy-(substituted phenylsulfonyl)alkanoic acid unit expressed bychemical formula (2). The PHA is synthesized, for example, using themicroorganisms with an ability to produce the PHA, which will bedescribed later. After biosynthesizing a PHA comprising a3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit expressed bychemical formula (7) that is a raw material for the PHA of the presentinvention, an oxidization reaction is carried out using an oxidizingagent, so as to synthesize the PHA of the present invention.

Moreover, the use of the above microorganisms under appropriateconditions enables to synthesize a copolymer comprising at least onetype selected from a group consisting of a 3-hydroxy-(substitutedphenylsulfinyl)alkanoic acid unit and a 3-hydroxy-(substitutedphenylsulfonyl)alkanoic acid unit, and another 3-hydroxyalkanoic acidunit. Specific examples of such a monomer unit may include: a3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit that is a rawmaterial for the PHA of the present invention; a 3-hydroxyalkanoic acidunit constituting an mcl-PHA, such as a 3-hydroxyhexanoic acid unit,3-hydroxyheptanoic acid unit, 3hydroxyoctanoic acid unit,3-hydroxynonanoic acid unit, 3-hydroxydecanoic acid unit,3-hydroxydodecanoic acid unit or 3-hydroxytetra acid unit; and a3-hydroxyalkanoic acid having an aromatic ring, such as a3-hydroxyphenylvaleric acid unit or 3-hydroxyphenoxyvaleric acid unit.Moreover, the PHA may comprise a plurality of these monomer units. Inthis case, using the characters of each monomer unit or functionalgroups contained therein, it is possible to control the physicalproperties of the PHA, to impart multiple functions to the PHA, and toexpress a new function by interaction among functional groups.

The polyhydroxyalkanoate comprising the unit expressed by the abovechemical formula (7) that is used as a starting material for the presentinvention is not particularly limited. It can be produced by aproduction method comprising a production process by microorganismshaving an ability to produce the PHA that will be described later, aproduction method using a plant/crop system into which a gene having anability to produce PHA is introduced, a production method by chemicalpolymerization, and other methods. Preferably, the production methodcomprising a production process by microorganisms is used.

A production method of the present invention in which apolyhydroxyalkanoate comprising the unit expressed by the above chemicalformula (7) as a starting material is used will be explained below.

The above polyhydroxyalkanoate as a starting material is produced by aproduction method, which is characterized in that the abovemicroorganisms are cultured in a medium containing at least one type ofω-(substituted phenylsulfanyl)alkanoic acid expressed by chemicalformula (16).

<Microorganisms Producing PHA>

The microorganism for use in the method of producingpolyhydroxyalkanoate containing units each expressed by chemical formula(7) as a starting material according to the present invention may be anymicroorganism as long as it is a microorganism capable of producing PHA,namely a microorganism capable of producing a PHA type polyestercontaining 3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unitseach expressed by general chemical formula (7) by culturing themicroorganism in a culture medium containing ω-(substitutedphenylsulfanyl)alkanoic acid expressed by chemical formula (16). Asuitable example of usable microorganisms capable of producing PHA maybe a microorganism belonging to Pseudomonas.

More specifically, among microorganisms belonging to Pseudomonas, morepreferable species as the microorganism for use in the production methodof the present invention may include Pseudomonas cichorii, Pseudomonasputida, Pseudomonas fluorecense, Pseudomonas oleovolans, Pseudomonasaeruginosa, Pseudomonas stutzeri and Pseudomonas jessenii.

Further, a more suitable strain includes, for example, Pseudomonascichorii YN2 (FERM BP-7375), Pseudomonas cichorii H45 (FERM BP-7374),Pseudomonas jessenii P161 (FERM BP-7376) and Pseudomonas putida P91(FERM BP-7373). These four types of strains are deposited on Nov. 20,2000 at the International Patent Organism Depositary (IPOD) of NationalInstitute of Advanced Industrial Science and Technology (AIST), TsukubaCentral 6, 1-1, Higashi 1-chome, Tsukuba-shi, Ibaraki-ken 305-8566,Japan, and described in Japanese Patent Application Laid-Open No.2001-288256 (Patent Document 16) and Japanese Patent ApplicationLaid-Open No. 2002-80751.

Moreover, other than these microorganisms belonging to Pseudomonasspecies, many types of microorganisms belonging to Burkholderia sp.,Aeromonas sp., Comamonas sp., etc., are known to produce an mcl-PHA orunusual PHA, and they can also be applied to the biosynthesis of the PHAof the present invention.

These microorganisms have an ability to produce a polyhydroxyalkanoatecomprising a ω-substituted-3-hydroxy-alkanoic acid as a monomer unit,from a raw material, ω-substituted-straight-chain alkanoic acidsubstituted with a 6-membered ring atomic group such as a substituted orunsubstituted phenyl group, substituted or unsubstituted phenoxy group,or substituted or unsubstituted cyclohexyl group on a side chainthereof, or ω-substituted-straight-chain alkanoic acid substituted witha 5-membered ring atomic group such as a thienyl group.

<Culture>

The above microorganisms are cultured in a medium containing at least acarbon source used as a substrate for introduction of a3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit, another carbonsource used as a substrate for introduction of a desired monomer unitother than the 3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit,and another carbon source for growth of the microorganisms, so as toproduce a PHA of interest. The produced PHA is generally an isotacticpolymer consisting only of an R form.

In the production method of the present invention, any culture mediummay be used for the culture medium for use in the process of culturing amicroorganism as long as the culture medium is an inorganic salt culturemedium containing a phosphate and a nitrogen source such as an ammoniumsalt or nitrate, and in the process of producing PHA in themicroorganism, the productivity of PHA can be improved by adjusting theconcentration of the nitrogen source.

In addition, nutrients such as an yeast extract, polypeptone and a meatextract can be added to the culture medium as a matrix for promoting thepropagation of the microorganism. That is, peptides may be added as anenergy source and a carbon source in the form of nutrients such as anyeast extract, polypeptone and a meat extract.

Alternatively, for the culture medium, saccharides, for example, aldosessuch as glyceroaldehyde, erythrose, arabinose, xylose, glucose,galactose, mannose and fructose, alditols such as glycerol, erythritoland xylitol, aldonic acids such as gluconic acid, uronic acids such asglucuronic acid and galacturonic acid, and disaccharides such asmaltose, sucrose and lactose may be used as an energy source and acarbon source consumed with propagation of the microorganism.

Instead of the above described saccharides, organic acids or saltsthereof, more specifically organic acids involved in the TCA cycle andorganic acids derived from a biochemical reaction with less steps by oneor two steps than the TCA cycle, or water soluble salts thereof may beused. As the organic acid or salt thereof, hydroxycarboxylic acids andoxocarboxylic acids such as pyruvic acid, oxalacetic acid, citric acid,isocitric acid, ketoglutaric acid, succinic acid, fumaric acid, malicacid and lactic acid or water soluble salts thereof can be used.Alternatively, amino acids or salts thereof, for example amino acidssuch as asparaginic acid and glutamic acid or salts thereof can be used.When the organic acid or salt thereof is added, it is more preferablethat one or more types are selected from a group consisting of pyruvicacid, oxalacetic acid, citric acid, isocitric acid, ketoglutaric acid,succinic acid, fumaric acid, malic acid, lactic acid and salts thereof,and are added to the culture medium and dissolved therein.Alternatively, when the amino acid or salt thereof is added, it is morepreferable that one or more types are selected from a group consistingof asparaginic acid, glutamic acid and salts thereof, and are added tothe culture medium and dissolved therein. At this time, as required, allor part thereof can be added in the form of a water soluble salt to bedissolved uniformly without affecting the pH of the culture medium.

It is desirable that the concentration of the above coexisting substrateadded to the culture medium as a carbon source for growth of themicroorganism and energy source for production of polyhydroxyalkanoateis usually selected so that it is in the range of from 0.05 to 5% (w/v),more preferably 0.2 to 2% (w/v) per culture medium. That is, forpeptides, yeast extracts, organic acids or salts thereof, amino acids orsalts thereof, and saccharides that are used as the above coexistingsubstrates, one or more types thereof may be added, and at this time, itis desirable that the total concentration of these added substrates iswith in the above described range of total concentrations.

Any carbon source may be used as a substrate for production of apolyhydroxyalkanoate of interest, as long as it can be converted intothe monomer unit by the used microorganisms. A preferred substrate isω-(substituted phenylsulfanyl)alkanoic acid expressed by chemicalformula (16). More specifically, examples of such a substrate mayinclude substituted phenylsulfanylbutyric acid, substitutedphenylsulfanylvaleric acid, substituted phenylsulfanylhexanoic acid andsubstituted phenylsulfanylheptanoic acid. Of these, in terms of thermalproperty, substituted phenylsulfanylbutyric acid, substitutedphenylsulfanylvaleric acid and substituted phenylsulfanylhexanoic acidare preferable. The ratio of content of these substrates is preferablywithin the range between 0.01% and 1% (w/v) per medium, and morepreferably between 0.02% and 0.2% (w/v) per medium.

Any inorganic salt culture medium can be used in the production methodof the present invention, as long as it contains components in whichmicroorganisms can grow, such as a phosphorus source (e.g., phosphate)or nitrogen source (e.g., ammonium salts or nitrate). Examples of suchan inorganic salt medium may include an MSB medium, an E medium (J.Biol. Chem., 218, 97-106 (1956)), and an M9 medium.

As one example, the composition of the inorganic salt culture medium (M9culture medium) used in Examples described later is shown below.

(Composition of M9 Culture Medium)

Na₂HPO₄: 6.3

KH₂PO₄: 3.0

NH₄Cl: 1.0

NaCl: 0.5

(by g/L, at pH=7.0).

Further, for ensuring satisfactory propagation of cells and associatedimprovement of productivity of PHA, an essential trace element such anessential trace metal element should be added in an appropriate amountto an inorganic salt culture medium such as the above described M9culture medium, and it is very effective to add about 0.3% (v/v) tracecomponent solution of which composition is shown below. The addition ofsuch a trace component solution supplies a trace metal element for usein propagation of the microorganism.

(Composition of Trace Component Solution)

nitrilotriacetic acid: 1.5; MgSO₄: 3.0; MnSO₄: 0.5; NaCl: 1.0; FeSO₄:0.1; CaCl₂: 0.1; CoCl₄: 0.1; ZnSO₄: 0.1; CuSO₄: 0.1; AlK(SO₄)₂: 0.1;H₂BO₃: 0.1; Na₂MoO₄: 0.1; NiCl₄: 0.1 (g/L).

Any temperature at which microorganism strains to be used can suitablybe propagated may be selected as a culture temperature, and anappropriate temperature is usually in the range of from about 15 to 37°C., more preferably from about 20 to 30° C.

Any culture method such as liquid culture and solid culture may be usedfor the culture as long as it allows propagation of microorganism andproduction of PHA. In addition, any type of culture method such as batchculture, fed-batch culture, semi-continuous culture and continuousculture may be used. Forms of liquid batch culture include a method ofsupplying oxygen while vibrating the microorganism in a vibration flask,and a method of supplying oxygen adopting a stirring ventilation systemwith a jar fermenter.

For the method of making the microorganism produce and accumulate PHA, atwo-step culture method in which the microorganism is cultured by twosteps may be adopted other than the one-step culture method in which themicroorganism is cultured in an inorganic salt culture medium containinga phosphate and a nitrogen source such as an ammonium salt or a nitratewith a matrix added therein in a predetermined concentration asdescribed above. In this two-step culture method, the microorganism isonce propagated sufficiently in the inorganic salt culture mediumcontaining a phosphate and a nitrogen source such as an ammonium salt ora nitrate with a matrix added therein in a predetermined concentrationas a primary culture, and thereafter cells obtained by the primaryculture are relocated to a culture medium with a matrix added therein ina predetermined concentration after limiting the amount of nitrogensource such as ammonium chloride contained in the culture medium, andare further cultured as a secondary culture, thereby making themicroorganism produce and accumulate PHA. Use of this two-step culturemethod may improve the productivity of desired PHA.

Generally, a produced PHA type polyester has reduced water solubilitybecause of the presence of hydrophobic atom groups such as aphenylsulfanyl group derived from a 3-hydroxy-(substitutedphenylsulfanyl)akanoic acid unit in the side chain, and is accumulatedin cells of the microorganism capable of producing PHA, and thereforecan easily be separated from the culture medium by collecting cellspropagated by culture and involved in production and accumulation thedesired PHA type polyester. After the collected cells are washed anddried, the desired PHA type polyester can be collected.

In addition, polyhydroxyalkanoate is usually accumulated in cells ofsuch a microorganism capable of producing PHA. For the method ofcollecting desired PHA from these microorganism cells, a method that isusually used may be adopted. For example, extraction with organicsolvents such as chloroform, dichloromethane and acetone is mostconvenient. Other than the above described solvents, dioxane,tetrahydrofuran and acetonitrile may be used. In addition, in a workingenvironment in which use of any organic solvent is not preferred, amethod in which in stead of solvent extraction, any one of a treatmentby surfactants such as SDS, a treatment by enzymes such as lysozyme, atreatment by chemicals such as hypochlorites, ammonium and EDTA, anultrasonic crashing method, a homogenizer method, a pressure crushingmethod, a bead impulse method, a grinding method, an immersion methodand a freeze-thaw method is used to physically crush microorganismcells, followed by removing cell components other than PHA to collectPHA may be adopted.

When the PHA of the present invention is produced using microorganisms,the produced PHA can contain monomer units other than the above3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit. Accordingly, apolymer may be designed in consideration of the functionality andphysical properties required of the polymer. Generally, a polymercomprising the above 3-hydroxy-(substituted phenylsulfanyl)alkanoic acidunit is expected to fully achieve the object of the present invention.However, if it is desired that the functionality and physical propertiesare widely controlled, it is also possible that the polymer comprisesmore types of monomer units, and it is preferable.

This is to say, not only a substrate for production of apolyhydroxyalkanoate of interest, that is, at least one type ofω-(substituted phenylsulfanyl)alkanoic acid expressed by chemicalformula (16) is used, but also at least one type of ω-substitutedalkanoic acid compounds expressed by chemical formula (17), at least onetype of ω-cyclohexylalkanoic acid compounds expressed by chemicalformula (18), or at least one type of ω-alkenoic acid compound expressedby chemical formula (19) is allowed to coexist with the above substrateduring culture, so that it is possible to produce a polyhydroxyalkanoatecomprising the 3-hydroxy-ω-substituted alkanoic acid unit expressed bychemical formula (20), the 3-hydroxy-ω-cyclohexylalkanoic acid unitexpressed by chemical formula (4) or the 3-hydroxy-ω-alkenoic acid unitexpressed by chemical formula (5) other than the 3-hydroxy-(substitutedphenylsulfanyl)alkanoic acid unit expressed by chemical formula (7). Inthis case, each of at least one type of the ω-(substitutedphenylsulfanyl)alkanoic acid expressed by chemical formula (16), atleast one type of the ω-substituted alkanoic acid compounds expressed bychemical formula (17), at least one type of the ω-cyclohexylalkanoicacid compounds expressed by chemical formula (18) and at least one typeof the ω-alkenoic acid compounds expressed by chemical formula (19) isselected preferably within the range between 0.01% and 1% (w/v) permedium, and more preferably within the range between 0.02% and 0.2% permedium.

Moreover, it is also possible to synthesize a copolymer comprising other3-hydroxyalkanoic acid units. A 3-hydroxyalkanoic acid unit constitutingan mcl-PHA, such as a 3-hydroxyhexanoic acid unit, 3-hydroxyheptanoicacid unit, 3-hydroxyoctanoic acid unit, 3-hydroxynonanoic acid unit,3-hydroxydecanoic acid unit, 3-hydroxydodecanoic acid unit or3-hydroxytetra acid unit may be a specific example of such a monomerunit. Furthermore, it is also possible that the PHA comprises aplurality of these monomer units. In this case, using the characters ofeach monomer unit or functional groups contained therein, it is possibleto control the physical properties of the PHA, to impart multiplefunctions to the PHA, and to express a new function by interaction amongfunctional groups.

<Synthesis of PHA of the Present Invention by Oxidization Reaction>

A polyhydroxyalkanoate comprising at least one type of unit selectedfrom a group consisting of the 3-hydroxy-(substitutedphenylsulfinyl)alkanoic acid unit expressed by chemical formula (1) andthe 3-hydroxy-(substituted phenylsulfonyl)alkanoic acid unit expressedby chemical formula (2) can be produced by selectively oxidizing asulfanyl group (—S—) that is a sulfur portion of the unit expressed bychemical formula (7) having the sulfanyl group (—S) as a phenylsulfanylgroup or substituted phenylsulfanyl group on a side chain terminalthereof. Thus, a polyhydroxyalkanoate comprising at least one type ofthe unit expressed by chemical formula (1) or (2) can be obtained.

With respect to such a oxidation treatment, some reagents e.g. peroxidecompound can be utilized. Any types of peroxide compound may be used asfar as it contributes to the object of the present invention, that is,oxidation of the sulfanyl group (—S—) present as a phenylsulfanyl groupor substituted phenylsulfanyl group. On this occasion, it is preferredto use in particular a peroxide compound selected from the groupconsisting of hydrogen peroxide, sodium percarbonate,metachloroperbenzoic acid, performic acid, and peracetic acid whentaking into consideration the efficiency of oxidation, influences on themain chain skeleton of PHA and copolymer containing it, simplicity oftreatment and so forth.

First, of those, treatment with hydrogen peroxide, which is easy in itstreating method, will be described. The simplest treating method withhydrogen peroxide is a method in which a microorganism is cultured underthe above-mentioned culture conditions and the microbial cells havingaccumulated therein PHA containing the unit of the chemical formula (7),i.e., a precursor of the PHA of the present invention, are suspended inhydrogen peroxide solution as they are and optionally heated andagitated for a predetermined period of time to treat the cells, and thenthe target PHA is recovered as an insoluble component. When theconcentration of hydrogen peroxide is relatively high or when thereaction temperature is relatively high, the insoluble component derivedfrom the microbial cells, for example, cell membrane may be oxidized tobe decomposed and solubilized while only the PHA of the presentinvention is recovered as insoluble component in a substantially pureform. On the other hand, under mild conditions, the decomposition andsolubilization of the insoluble component are not performed sufficientlyand the step of disrupting living cells derived from the microbial cellsmay partly remain.

Upon utilizing such mild conditions, it is possible to apply a method inwhich cultured microbial cells are disrupted in advance, the insolublecomponent derived from the microbial cells is removed, PHA containingthe unit of the chemical formula (7), which is a precursor of PHA of thepresent invention, is recovered as a crude product, then treated withhydrogen peroxide solution. By adopting the method including the step ofdisrupting cultured microbial cells in advance and separating andrecovering the intermediate raw material (precursor) PHA, PHA havingsufficiently high purity can be recovered even when the treatment withhydrogen peroxide solution is performed under relatively mildconditions.

In the method of producing the PHA according to the present invention,it is preferred that the step of disrupting living cells as describedabove is performed by means using no chemicals for disrupting cellmembranes, such as a supersonic wave disrupting method, a homogenizermethod, a pressure disrupting method, a bead impact method, atriturating method, a grinding method (in which cells are ground in amortar with addition of an auxiliary agent such as glass powder oralumina powder), and a freezing and thawing method. After the step ofdisrupting living cells, the separated insoluble component isresuspended and subjected to centrifugation or the like to separate asolid component and a soluble component from each other, and only thesolid component, which contains the PHA component serving as anintermediate raw material is treated with hydrogen peroxide.

Further, another method for separating PHA includes a method in whichafter the culture step only PHA is extracted and isolated from PHAaccumulating microbial cells by utilizing a means for extraction andisolation with a solvent in which the accumulated PHA is soluble, suchas chloroform, dichloromethane or acetone, and after the extraction andisolation, only the obtained PHA is treated with hydrogen peroxide. Inthis method of utilizing solvent extraction, the precursor PHA extractedand recovered from microbial cells tends to become agglomerate in anaqueous medium in which treatment with hydrogen peroxide is performed.The agglomerated precursor PHA frequently involves concomitantdifficulty and troubles in operation; for example, its contact with aperoxide compound such as hydrogen peroxide is prevented and in somecases the efficiency of the oxidation reaction may be significantlyreduced. From this standpoint, the two methods as earlier described areconvenient in operation because the precursor PHA originally exists inthe form of fine particles in the microbial cell so that in such a statefine particulate precursor PHA can be subjected to the treatment withhydrogen peroxide as a suspension in water.

In the method of producing the PHA according to the present invention,the hydrogen peroxide utilized as an oxidizing agent may be used in anyform as far as it can attain the object of the present invention, thatis, oxidation of the sulfanyl group (—S—) present as a phenylsulfanylgroup or substituted phenylsulfanyl group. From the standpoint ofcontrolling production processes, it is desirable to use a hydrogenperoxide solution whose concentration is in a stable state, for example,hydrogen peroxide dissolved in an aqueous solvent. For example, ahydrogen peroxide solution according to JIS K-8230, which can beproduced stably on an industrial scale in large amounts, may berecommended. For example, hydrogen peroxide solution prepared byMitsubishi Gas Chemical Company, Inc. (containing 31% of hydrogenperoxide) is a preferred solution of hydrogen peroxide in the method ofthe present invention.

In the method for producing the PHA according to the present invention,the conditions of the oxidation treatment with the hydrogen peroxide mayvary depending on the state of PHA to be treated (whether or notmicrobial cell components are present, whether or not it is agglomeratedor in a state of fine particules, etc.), but it is preferred to selectthe conditions approximately within the range described below.Generally, when the residual amount of microbial cell components issmall, or when the form of the precursor PHA is particulate, oxidationand solubilization of unnecessary microbial cell components areperformed readily or the particulate PHA itself is treated more quickly,and thus milder conditions may be used. When utilizing theabove-mentioned JIS K-8230 standard preparation hydrogen peroxidesolution (containing 31% of hydrogen peroxide), the dilution condition(concentration), use amount, treating temperature, treating time and soforth may be selected within the ranges described below. Concentrationof hydrogen peroxide in the treating solution: depending on reactiontemperature; from 8% (about 4 fold dilution) to 31% (stock solution), amore preferred concentration range being from 16% (about 2-folddilution) to 31% (stock solution); Reaction amount: depending on theratio of the units of the chemical formula (7) contained in theprecursor PHA; from 30 mL to 500 mL in terms of the stock solution ofhydrogen peroxide solution (containing 31% of hydrogen peroxide) per 1 gof PHA before the treatment, a more preferred reaction amount beingwithin the range of from 100 mL to 300 mL; Reaction temperature:depending on the concentration of hydrogen peroxide in the treatingsolution; from 30° C. to 100° C., a more preferred temperature beingselected to fall within the range of from 80° C. to 100° C.; andReaction time: depending on the reaction temperature; from 10 minutes to180 minutes, a more preferred reaction time being within the range offrom 30 minutes to 120 minutes.

Treatment with hydrogen peroxide performed under the conditions withinthe ranges described above converts the precursor PHA containing theunit of the chemical formula (7) which is accumulated in the microbialcell into a PHA containing in the polymer molecule thereof at least oneof the units of the chemical formulae (1) and (2), or a PHA thatcontains in addition to the units of the chemical formulae (1) and/or(2) the unit of the chemical formula (7) derived from the intermediateraw material PHA. On this occasion, by selecting the reaction conditionsof the treatment with hydrogen peroxide to control a rate at whichoxidation proceeds and a reaction amount, the existence ratio of theunits of three types described above can be regulated.

Next, the method in which metachloroperbenzoic acid (MCPBA) is used asthe peroxide compound will be described.

When MCPBA is used, the oxidation of sulfanyl group (—S—) that exists asa phenylsulfanyl group or substituted phenylsulfanyl group proceedsstoichiometrically, so that it is easy to control the content ratios ofthe units of the chemical formulae (1) and (2). Also, since the reactionconditions are mild, unnecessary side reactions such as cleavage of PHAmain chain backbone, crosslinking reaction at the active site and thelike are prevented from easily occurring. Therefore, in the method forthe production of PHA according to the present invention,metachloroperbenzoic acid (MCPBA) is one of very suitable peroxidecompounds for selectively producing the target PHA.

As for the general reaction conditions for selectively oxidizing asulfanyl group (—S—) into a sulfinyl group (—SO—), the reaction isperformed in chloroform with the amount of MCPBA being selected to beslightly in excess of 1 mole per mole of the unit containing a sulfanylgroup (—S—) in the intermediate raw material PHA (precursor),specifically from the range of from 1.1 to 1.4 moles, at a temperatureselected from the range of from 0° C. to 30° C. Under the oxidationconditions as described above, the reaction can proceed up toapproximately 90% of the stoichiometric value when the reaction time isso set as to be about 10 hours and up to approximately 100% ofstoichiometric value when the reaction time is so set as to be about 20hours.

To oxidize all the sulfanyl groups (—S—) to sulfonyl groups (—SO₂—), thereaction may be performed with the amount of MCPBA being selected to beslightly in excess of 2 moles per mole of the unit containing a sulfanylgroup (—S—) in the intermediate raw material PHA (precursor),specifically, in the range of from 2.1 to 2.4 moles, under the samesolvent, temperature and time conditions as those described above.

Moreover, a method of using permanganate will be explained as an exampleof using other compounds as a peroxide compound. Potassium permanganateis common as the above described permanganate used as an oxidizingagent. The use amount of permanganate may be usually at least 1 molequivalent, and preferably 2 to 10 mol equivalent with respect to 1 molof the unit comprising a phenylsulfanyl group expressed by chemicalformula (7).

Various types of inorganic acids or organic acids such as sulfuric acid,hydrochloric acid, acetic acid or nitric acid are generally used to seta reaction system under an acidic condition. However, when acid such assulfuric acid, nitric acid or hydrochloric acid is used, there is a riskthat the ester bond of the main chain of a polyhydroxyalkanoate might becleaved, resulting in decrease of the molecular weight. Accordingly,acetic acid is preferably used. The use amount of acid is generallywithin the range of 0.2 to 2,000 mol equivalent, and preferably 0.4 to1,000 mol equivalent with respect to 1 mol of the unit comprising aphenylsulfanyl group expressed by chemical formula (7). If the usedamount is less than 0.2 mol equivalent, it results in low yield. If itexceeds 2,000 mol equivalent, decomposed matter is generated by acid asa by-product. Thus, both cases are not preferable. Moreover, crown-ethercan be used to promote the reaction. In such a case, crown-ether andpermanganate form a complex, thereby obtaining an effect to increasereaction activity. Examples of a commonly used crown-ether includedibenzo-18-crown-6-ether, dicyclo-18-crown-6-ether, and18-crown-6-ether. The use amount of crown-ether is usually 0.005 to 2.0mol equivalent, and preferably 0.01 to 1.5 mol equivalent with respectto 1 mol of permanganate.

A solvent used in the oxidization reaction of the present invention isnot particularly limited, as long as it is inactive to the reaction.Examples of a solvent to be used may include water; acetone; ethers suchas tetrahydrofuran or dioxane; aromatic hydrocarbons such as benzene,toluene or xylene; aliphatic hydrocarbons such as hexane or heptane; andhalogenated hydrocarbons such as methyl chloride, dichloromethane orchloroform. Of these, halogenated hydrocarbons such as methyl chloride,dichloromethane or chloroform and acetone are preferable in terms of thesolubility of the polyhydroxyalkanoate.

In the above oxidization reaction of the present invention, thepolyhydroxyalkanoate comprising the unit expressed by chemical formula(7), permanganate and acid may be fed to a reaction system together witha solvent from the beginning of the reaction, or each of these compoundsmay be added to the reaction system continuously or intermittentlyduring the reaction. Otherwise, it may be possible that onlypermanganate has previously been dissolved or suspended in a solvent andthat the polyhydroxyalkanoate and acid are then added to the reactionsystem continuously or intermittently during the reaction, or it may bealso possible that only the polyhydroxyalkanoate has previously beendissolved or suspended in a solvent and that permanganate and acid arethen added to the reaction system continuously or intermittently duringthe reaction. Moreover, it may also be possible that thepolyhydroxyalkanoate and acid have previously been fed to the reactionsystem and that permanganate is then added thereto continuously orintermittently during the reaction. Furthermore, it may also be possiblethat permanganate and acid have previously been fed to the system andthat the polyhydroxyalkanoate is then added thereto continuously orintermittently during the reaction. Still further, it may also bepossible that the polyhydroxyalkanoate and permanganate have previouslybeen fed to the system and that acid is then added thereto continuouslyor intermittently during the reaction.

The reaction temperature is usually between −20° C. and 40° C., andpreferably 0° C. and 30° C. The reaction time depends on thestoichiometric ratio of the unit expressed by chemical formula (7) andpermanganate and the reaction temperature, but it is usually 2 to 48hours.

A precursor polyhydroxyalkanoate comprising the unit expressed bychemical formula (7) can be converted into a polyhydroxyalkanoatecomprising in a molecule thereof at least one type selected from a groupconsisting of units expressed by chemical formulas (1) and (2) bytreating the phenylsulfanyl group expressed by chemical formula (7) withan oxidizing agent. The polyhydroxyalkanoate produced by the method ofthe present invention having a polyhydroxyalkanoate produced bymicroorganisms as an intermediate material comprises, in a moleculethereof, a unit having at least one of a sulfinyl structure (—SO—) and asulfonyl structure (—SO₂—). These structures strongly promote thelocalization of electrons in a molecule at the unit terminal. There is apossibility that the electric property of the polyhydroxyalkanoate ofthe present invention significantly differs from that of theconventional polyhydroxyalkanoate. Moreover, because of the localizationof electrons, its manner to a solvent also differs from that of theconventional polyhydroxyalkanoate. For example, the polyhydroxyalkanoateof the present invention is soluble in a polar solvent such asdimethylformamide (DMF). Moreover, the inventive polyhydroxyalkanoatehas remarkably controlled thermal properties such as an increased glasstransition temperature as a typical example, and therefore it can beapplied to a wide range of uses.

Furthermore, a polyhydroxyalkanoate copolymer comprising a unit having acarboxyphenyl group that is a structure expressed by chemical formula(3) and a unit expressed by chemical formula (6) can be obtained byoxidizing with an oxidizing agent a carbon-carbon double bond portion ora methyl group portion in a vinylphenyl group or methylphenyl group thatis a structure expressed by chemical formula (20) or a terminal vinylgroup expressed by chemical formula (5). Examples of known methods ofobtaining carboxylic acid by oxidizing a carbon-carbon double bond ormethyl group with an oxidizing agent may include a method of usingpermanganate (J. Chem. Soc., Perkin. Trans. 1, 806 (1973)), a method ofusing dichromate (Org. Synth., 4, 698 (1963)), a method of usingperiodate (J. Org. Chem., 46, 19 (1981)), a method of using nitric acid(Japanese Patent Application Laid-Open No. 59-190945), and a method ofusing ozone (J. Am. Chem. Soc., 81, 4273 (1959)). Moreover, with regardto polyhydroxyalkanoate, the above Macromolecular chemistry, 4, 289-293(2001) discloses a method of obtaining carboxylic acid by oxidizing acarbon-carbon double bond located at the side chain terminal of thepolyhydroxyalkanoate with potassium permanganate as an oxidizing agentunder an acidic condition. The same above method can be applied in thepresent invention.

Potassium permanganate is common as the above permanganate used as anoxidizing agent. Since the oxidization reaction is a stoichiometricreaction, the use amount of permanganate may be usually at least 1 molequivalent, and preferably 2 to 10 mol equivalent with respect to 1 molof the unit comprising a vinylphenyl or methylphenyl group that is astructure expressed by chemical formula (20), or to 1 mol of the unitexpressed by chemical formula (5).

Various types of inorganic acids or organic acids such as sulfuric acid,hydrochloric acid, acetic acid or nitric acid are generally used to seta reaction system under an acidic condition. However, when acid such assulfuric acid, nitric acid or hydrochloric acid is used, there is a riskthat the ester bond of the main chain of a polyhydroxyalkanoate might becleaved, resulting in decrease of the molecular weight. Accordingly,acetic acid is preferably used. The use amount of acid is generallywithin the range of 0.2 to 2,000 mol equivalent, and preferably 0.4 to1,000 mol equivalent with respect to 1 mol of the unit comprising avinylphenyl or methylphenyl group that is a structure expressed bychemical formula (20) or 1 mol of the unit expressed by chemical formula(5). If the used amount is less than 0.2 mol equivalent, it results inlow yield. If it exceeds 2,000 mol equivalent, decomposed matter isgenerated by acid as a by-product. Thus, both cases are not preferable.Moreover, crown-ether can be used to promote the reaction. In such acase, crown-ether and permanganate form a complex, thereby obtaining aneffect to increase reaction activity. Examples of a commonly usedcrown-ether include dibenzo-18-crown-6-ether, dicyclo-18-crown-6-ether,and 18-crown-6-ether. The use amount of crown-ether is usually 0.005 to2.0 mol equivalent, and preferably 0.01 to 1.5 mol equivalent withrespect to 1 mol of permanganate.

A solvent used in the oxidization reaction of the present invention isnot particularly limited, as long as it is inactive to the reaction.Examples of a solvent to be used may include water; acetone; ethers suchas tetrahydrofuran or dioxane; aromatic hydrocarbons such as benzene,toluene or xylene; aliphatic hydrocarbons such as hexane or heptane; andhalogenated hydrocarbons such as methyl chloride, dichloromethane orchloroform. Of these, halogenated hydrocarbons such as methyl chloride,dichloromethane or chloroform and acetone are preferable in terms of thesolubility of the polyhydroxyalkanoate.

In the above oxidization reaction of the present invention, apolyhydroxyalkanoate copolymer comprising the unit expressed by chemicalformula (7) and the unit expressed by chemical formula (20) or (5),permanganate and acid may be fed to a reaction system together with asolvent from the beginning of the reaction, or each of these compoundsmay be added to the reaction system continuously or intermittentlyduring the reaction. Otherwise, it may be possible that onlypermanganate has previously been dissolved or suspended in a solvent andthat the polyhydroxyalkanoate copolymer and acid are then added to thereaction system continuously or intermittently during the reaction, orit may be also possible that only the polyhydroxyalkanoate copolymer haspreviously been dissolved or suspended in a solvent and thatpermanganate and acid are then added to the reaction system continuouslyor intermittently during the reaction. Moreover, it may also be possiblethat the polyhydroxyalkanoate copolymer and acid have previously beenfed to the reaction system and that permanganate is then added theretocontinuously or intermittently during the reaction. Furthermore, it mayalso be possible that permanganate and acid have previously been fed tothe system and that the polyhydroxyalkanoate copolymer is then addedthereto continuously or intermittently during the reaction. Stillfurther, it may also be possible that the polyhydroxyalkanoate copolymerand permanganate have previously been fed to the system and that acid isthen added thereto continuously or intermittently during the reaction.

The reaction temperature is usually between −20° C. and 40° C., andpreferably 0° C. and 30° C. The reaction time depends on thestoichiometric ratio between the units expressed by chemical formula (7)and chemical formula (20) or (5) and permanganate, and the reactiontemperature, but it is usually 2 to 48 hours.

A precursor polyhydroxyalkanoate copolymer comprising the unit expressedby chemical formula (7) can be converted into a polyhydroxyalkanoatecomprising in a molecule thereof at least one type selected from a groupconsisting of units expressed by chemical formulas (1) and (2), or intoa polyhydroxyalkanoate copolymer still comprising the unit expressed bychemical formula (7) derived from the polyhydroxyalkanoate as anintermediate material as well as the units expressed by chemicalformulas (1) and (2). At the same time, the precursorpolyhydroxyalkanoate copolymer can be simultaneously converted into apolyhydroxyalkanoate copolymer comprising, in a molecule thereof, a unitcomprising a carboxyl group as well as the units expressed by chemicalformulas (1) and (2) by treating with an oxidizing agent a carbon-carbondouble bond portion or methyl group portion in a vinylphenyl group ormethylphenyl group that is a structure expressed by chemical formula(20) or a terminal vinyl group expressed by chemical formula (5).

<Resin Composition and Molded Article>

The PHA obtained by the above method is subjected to molding orprocessing as necessary, so as to obtain a molded article with a desiredform.

The above PHA can be singly used as a biodegradable resin composition,but it can also be blended with other resin components depending onpurposes within the range where desired properties are maintained.Regarding the mixing ratio of the PHA and a thermoplastic resin, it ispreferable that the content of the PHA is larger than that of thethermoplastic resin. Specific examples of resin components may include apolyester resin, a polystyrene resin, a polypropylene resin, apolyethylene terephthalate resin, a polyurethane resin, a polyvinylresin, and a polyamide resin. Of these, when a polyester resin such aspoly-ε-caprolactone or polylactic acid is used, a resin composition withexcellent biodegradability can be obtained. However, even when otherresin compositions such as polystyrene are used, it is possible toimprove biodegradability by applying the method of the presentinvention. This is because the PHA of the present invention contained ina molded article that is obtained by blending the above PHA with theabove resin is quickly decomposed in the natural environment, the moldedarticle is thereby quickly decomposed, and because the blended resinalso easily undergoes photolysis or biodegradation.

Moreover, resin additives can be added to the resin composition asnecessary. Examples of such additives may include a plasticizer, a heatstabilizer, a lubricant, an antiblocking agent, a nuclear agent, aphotolysis promoting agent, a biodegradation promoting agent, anantioxidant, an ultraviolet stabilizer, an antistatic agent, a flameretardant, a dropping agent, an antimicrobial agent, a deodorant, afiller, a coloring agent, and a mixture thereof.

Specific examples of a plasticizer may include an aliphatic dibasic acidester, a phthalate ester, a hydroxypolycarboxylic acid ester, apolyester plasticizer, a fatty acid ester, an epoxy plasticizer, and amixture thereof. The additive amount of such a plasticizer is differentdepending on purposes, but it is appropriate to add 3 to 30 parts bymass of plasticizer with respect to 100 parts by mass of resincomposition.

A specific example of a heat stabilizer may include aliphaticcarboxylate. More specific examples may include salts of sodium,calcium, aluminum, barium, magnesium, manganese, iron, zinc, lead,silver or copper, such as lactic acid or hydroxybutyric acid. Theadditive amount of such a heat stabilizer is preferably 0.5 to 10 partsby mass with respect to 100 parts by mass of resin composition.

Specific examples of a lubricant may include a fatty acid ester, ahydrocarbon resin, paraffin, higher fatty acid, oxy fatty acid, fattyacid amide, alkylene bis fatty acid amide, aliphatic ketone, a fattyacid lower alcohol ester, a fatty acid polyhydric alcohol ester, a fattyacid polyglycol ester, aliphatic alcohol, polyhydric alcohol,polyglycol, polyglycerol, a metallic soap, a denatured silicon, and amixture thereof. The additive amount of such a lubricant is preferably0.05 to 5 parts by mass with respect to 100 parts by mass of resincomposition.

Specific examples of a photolysis promoting agent may include benzoins,benzoin alkyl ethers, benzophenones and derivatives thereof such asbenzophenone or 4,4-bis(dimethylamino)benzophenone, acetophenones andderivatives thereof such as acetophenone or α,α-diethoxyacetophenone,quinones, thioxantones, an agent for photoexcitation such asphthalocyanine, anatase titanium oxide, an ethylene-carbon monoxidecopolymer, and a sensitizer consisting of aromatic ketone and metalsalts. Moreover, two or more of these photolysis promoting agents can beused in combination.

Specific examples of a biodegradation promoting agent may includeorganic acids such as glycolic acid, lactic acid, citric acid, tartaricacid, malic acid, oxalic acid, malonic acid, succinic acid, succinicanhydride or glutaric acid, and coconut shell activated carbon.Moreover, two or more of these biodegradation promoting agents can beused in combination.

Mn of the thus obtained resin composition comprising the PHA as a maincomponent is preferably between 1,000 and 1,000,000.

The resin composition of the present invention can be used formechanical parts, electrical or electronic components, various types ofheating apparatuses, wrapping containers, automotive parts, etc., towhich the conventional mcl PHA or unusual PHA has not been appliedbecause of their thermal properties. For example, food wrappingcontainers are produced by any method selected from a group consistingof foam extrusion molding, nondrawn extruded sheet molding,biaxially-stretched extruded sheet molding, injection hollow molding,and injection molding, followed by postforming processing as necessary.

For example, in the case of foam extrusion molding, a melted resin isimpregnated with gas as a foaming agent to form a foaming sheet, and itis then molded into a tray for perishable foodstuff, or bowl-shaped orhorned container for instant needle. The obtained foaming sheet ispostformed into a desired shape, so as to obtain a food wrappingmaterial of interest in the present invention. Moreover, other foodwrapping materials of interest such as a lunch box, lids thereof or foodpackages are obtained by forming a sheet with or without performing adrawing process, and then performing a postforming on the obtainedsheet. Food containers or cups obtained by injection hollow molding orinjection molding are also included in the above food wrappingcontainers.

Application to Toner

The polyhydroxyalkanoate of the present invention is applied to anelectrostatic latent image developing toner and an image formationprocess using the same. More specifically, the inventivepolyhydroxyalkanoate can be used as a raw material for a binder resinconstituting the majority of the substantial part of the toner otherthan pigments.

That is to say, the present invention relates to a binder resincomprising the above polyhydroxyalkanoate, and further, it relates to anelectrostatic latent image developing toner comprising the binder resin.Furthermore, the present invention relates to an image forming method,which comprises an electrification step of applying a voltage to anelectrification member from the outside to uniformly electrify anelectrostatic latent image carrier, a development step of forming atoner image on the electrified electrostatic latent image carrier, atransferring step of transferring the toner image on the electrifiedelectrostatic latent image carrier to an object transfer material withor without an intermediate transferring member, and a heat-fixation stepof heat-fixing the toner image on the material. Still further, thepresent invention relates to an image forming apparatus having eachmeans corresponding to the above each step of the above method, that is,electrification means, development means, transferring means, andheat-fixation means.

<Binder Resin>

For the binder resin of the present invention, the abovepolyhydroxyalkanoate may be directly used, but the binder resin may alsocomprise other thermoplastic resins typically including biodegradableresins such as polycaprolactone or polylactic acid. When the numberaverage molecular weight of the PHA is less than 300,000, the PHA hasgood solubility in each of polycaprolactone and polylactic acid, andtherefore a transparent and colorless melted polymer blend body isobtained. Thus, low number average molecular weight is preferable. Incontrast, when the PHA has a relatively high number average molecularweight such as more than 500,000, it does not have good solubility, andso the obtained melted polymer blend body has an unfavorable color.However, even in this case, if the molecular weight is decreased to lessthan 300,000 by mixing under a high shearing force for example, thesolubility is improved, and a transparent and colorless melted polymerblend body can be obtained.

The number average molecular weight of the binder resin of the presentinvention is preferably between 2,000 and 300,000. Further, in order toexpress functions as a binder resin, the glass transition point of thebinder resin of the present invention is preferably between 30° C. and80° C., and the softening point is preferably between 60° C. and 170° C.

The PHA has a basic skeleton as a biodegradable resin, and is thereforecapable of being used for producing various kinds of products throughmelt-processing and the like, as in the case of conventional plastics,and it also has a remarkable characteristic such that it is decomposedby organisms and involved in the material cycle in the natural world,unlike synthetic polymers derived from oil. Therefore, the compoundrequires no combustion process, and it is an effective material in thesense that it contributes to prevention of air pollution and globalwarming. The compound can be used as a plastic enabling preservation ofenvironments.

Moreover, the PHA is easily hydrolyzed in the presence of alkalinewater. Accordingly, it has an advantage in that it efficientlyeliminates a toner containing pigments such as carbon black from printedpapers.

In a case where the PHA of the present invention is used as a binderresin, its glass transition temperature is preferably between 30° C. and80° C., more preferably between 40° C. and 80° C., and particularlypreferably between 50° C. and 70° C. If the glass transition temperatureis lower than 30° C., the blocking property of the binder resin islikely to become poor, and if it is higher than 80° C., its fixabilityis likely to become poor. In addition, the softening point of the PHAof-the present invention is preferably between 60° C. and 170° C., andparticularly preferably between 80° C. and 140° C. If the softeningpoint is lower than 60° C., the anti-offset property is likely todeteriorate, and if it is higher than 170° C., the fixing temperature islikely to rise.

Moreover, when the PHA is used as a binder resin, its number averagemolecular weight Mn is preferably between 2,000 and 300,000, morepreferably between 2,000 and 150,000, and particularly preferablybetween 5,000 and 100,000. If the Mn is less than 2,000, the glasstransition temperature is significantly decreased, and it might resultin deterioration of the anti-blocking property. If it exceeds 300,000,viscosity is increased during the melting process, and it might resultin deterioration of the low-temperature fixability.

Commercially available products, e.g., Lacty (product name) manufacturedby Shimadzu Corporation, can be preferably used as thermoplastic resinssuch as polylactic acid that can be added to the PHA of the presentinvention. In addition, those obtained by various types ofpolymerization methods can also be used. Moreover, any given resins thatwill be described later in “Binder resin” can also be mixed into thePHA.

<Other Constitutional Materials>

Other constitutional materials constituting the electrostatic latentimage developing toner of the present invention will be explained below.The electrostatic latent image developing toner of the present inventioncomprises a coloring agent, an electrical charge controlling agent, andother additives that are added as necessary, as well as the above binderresin.

(Binder Resin: Components other than PHA)

The binder resin of the present invention can be preferably used as abinder resin. However, thermoplastic resins other than the binder resinof the present invention can also be contained in the binder resin. Forexample, the binder resin of the present invention can be mixed withpolystyrene, polyacrylic acid ester, a styrene-acrylic acid estercopolymer, polyvinyl chloride, polyvinyl acetate, polyvinylidenechloride, a phenol resin, an epoxy resin, or a polyester resin. Such athermoplastic resin is not particularly limited, and any thermoplasticresin can be used with the binder resin of the present invention, aslong as it is commonly used for the production of a toner. When athermoplastic resin having no biodegradability is used as a binder resinother than PHA, the mixing ratio of other thermoplastic resins ispreferably less than 50% by mass with respect to the total binder resin.If the mixing ratio of other thermoplastic resins is more than 50% bymass, other binder resins have too strong binding strength to thesurface of a paper, thereby decreasing the deinking ability. Moreover,when the resin is used as a biodegradable toner, it is preferable not toadd other thermoplastic resins with no biodegradability thereto.

(Other Biodegradable Plastics)

In addition, in the present invention, various commercially availablebiodegradable plastics are preferably used. Examples of thebiodegradable plastics are “Ecostar”, “Ecostar plus” (produced byHagiwara Industries, Inc.), “Biopole” (produced by Monsanto Company),“Ajicoat” (Ajinomoto Co., Ltd.), “Placcel”, “Polycaprolactone” (producedby Daicel Chem., Ind., Ltd.), “SHOWLEX”, “Bionolle” (produced by ShowaDenko K.K.), “Lacty” (produced by Shimadzu Corporation), “Lacea”(produced by Mitsui Chemicals, Inc.) and the like. When these resins areused as a mixture, bioderadability that is the characteristic of thetoner of the present invention will not be damaged.

Of these, polycaprolactone (i.e., an ε-caprolactone copolymer) or theabove polylactic acid is particularly preferable in that these compoundsare easily and completely decomposed by lipase, esterase, etc., and inthat they are easily blended with other resins and their physicalproperties are easily modified by copolymerization or the like.

(Specific Examples of other Resins)

Examples of the styrene-based polymer include copolymers of styrene and(meth)acrylic acid ester, copolymers of these monomers and other monomercopolymerizable therewith, copolymers of styrene and a diene-basedmonomer (butadiene, isoprene or the like) and copolymers of thesemonomers and other monomers copolymerizable therewith, and the like. Thepolyester-based polymer includes polycondensation products between anaromatic dicarboxylic acid and an alkylene oxide adduct of an aromaticdiol and the like. The epoxy-based polymer includes reaction productsbetween an aromatic diol and epichlorohydrin and modified productsthereof and the like. The polyolefin-based polymer includespolyethylene, polypropylene and copolymer chains of these and othermonomers copolymerizable therewith, and the like. The polyurethane-basedpolymer includes polyaddition products between an aromatic diisocyanateand an alkylene oxide adduct of an aromatic diol and the like.

Specific examples of the binder resin used in combination with theelectrical charge controlling agent of the present invention or inmixture with the binder resin of the present invention include polymersof polymerizable monomers described below, mixtures of these orcopolymerization products obtained by using two or more polymerizablemonomers described below. Specifically, such polymers include, forexample, styrene-based polymers such as styrene/acrylic acid copolymers,or styrene/methacrylic acid-based copolymers, polyester-based polymers,epoxy-based polymers, polyolefin-based polymers, polyurethane-basedpolymers and the like, which are suitably used.

Specific examples of the polymerizable monomer includes styrene andderivatives of styrene, for example, styrene; styrene derivatives, suchas o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene,p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene,2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene,p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene,and p-n-dodecylstyrene; ethylenically unsaturated monoolefins, such asethylene, propylene, butylene, and isobutylene; unsaturated polyenes,such as butadiene; vinyl halides, such as vinyl chloride, vinylidenechloride, vinyl bromide, and vinyl fluoride; vinyl esters, such as vinylacetate, vinyl propionate, and vinyl benzoate; α-methylene-aliphaticmonocarboxylic acid esters, such as methyl methacrylate, ethylmethacrylate, propyl methacrylate, methacrylate, n-butyl methacrylate,isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate,2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate,dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate;acrylic acid esters, such as methyl acrylate, ethyl acrylate, n-butylacrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecylacrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethylacrylate, and phenyl acrylate; vinyl ethers, such as vinyl methyl ether,vinyl ethyl ether, and vinyl isobutyl ether; vinyl ketones, such asvinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone;N-vinyl compounds, such as N-vinylpyrrole, N-vinylcarbazole,N-vinylindole, and N-vinylpyrrolidone; vinylnaphthalenes; acrylic acidor methacrylic acid derivatives, such as acrylonitrile,methacrylonitrile, and acrylamide; dicarboxylic acids, such as maleicacid, phthalic acid, succinic acid, terephthalic acid; esters of theabove-mentioned α,β-unsaturated esters and diesters of dibasic acidssuch as methyl maleate, butyl maleate, and dimethyl maleate; polyolcompounds, such as ethylene glycol, diethylene glycol, triethyleneglycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol,1,6-hexanediol, bisphenol A, hydrogenated bisphenol A, andpolyoxyethylenated bisphenol A; isocyanates, such as p-phenylenediisocyanate, p-xylylene diisocyanate, and 1,4-tetramethylenediisocyanate; amines, such as ethylamine, butylamine, ethylenediamine,1,4-diaminobenzene, 1,4-diaminobutane, and monoethanolamine; epoxycompounds, such as diglycidyl ether, ethylene glycol diglycidyl ether,bisphenol A glycidyl ether, and hydroquinone diglycidyl ether; and soforth.

(Crosslinking Agent)

In the case of forming a binder resin, which is used in combination withthe electrical charge controlling agent of the present invention or inmixture with the binder resin of the present invention, crosslinkingagents described below may be used as necessary. Examples of thebifunctional crosslinking agent include divinylbenzene,bis(4-acryloxypolyethoxyphenyl)propane, ethylene glycol diacrylate,1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate,1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycoldiacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate,tetraethylene glycol diacrylate, polyethylene glycol #200 diacrylate,polyethylene glycol #400 diacrylate, polyethylene glycol #600diacrylate, dipropylene glycol diacrylate, polypropylene glycoldiacrylate, polyester type diacrylates (MANDA, trade name; availablefrom Nippon Kayaku Co., Ltd.), and the above diacrylates whose acrylatemoiety has been replaced with dimethacrylate.

More than bifunctional, that is, polyfunctional cross-linking agents mayinclude pentaerythritol triacrylate, trimethylolethane triacrylate,trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate,oligoester acrylate, and the above compounds whose acrylate moiety hasbeen replaced with methacrylate, and also2,2-bis(4-methacryloxypolyethoxyphenyl)propane, diallyl phthalate,triallyl cyanurate, triallyl azo cyanurate, triallyl isocyanurate anddiaryl chlorendate.

(Polymerization Initiator)

In the case of forming a binder resin, which is used in combination withthe electrical charge controlling agent of the present invention or inmixture with the binder resin of the present invention, polymerizationinitiators described below may be used as necessary. The polymerizationinitiator includes, for example, t-butyl peroxy-2-ethylhexanoate, cumeneperpivalate, t-butyl peroxylaurate, benzoyl peroxide, lauroyl peroxide,ocatanoyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumylperoxide, 2,2′-azobisisobutyronitrile,2,2′-azobis(2-methylbutyronitrile),2,2′-azobis(2,4-dimethylvaleronitrile),2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile),1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane,1,1-bis(t-butylperoxy)cyclohexane,1,4-bis(t-butylperoxycarbonyl)cyclohexane, 2,2-bis(t-butylperoxy)octane,n-butyl-4,4-bis(t-butylperoxy)valerate, 2,2-bis(t-butylperoxy)butane,1,3-bis(t-butylperoxyisopropyl)benzene,2,5-dimethyl-2,5-di(t-butylperoxy)hexane,2,5-dimethyl-2,5-di(t-butylperoxy)hexane,2,5-dimethyl-2,5-di(benzoylperoxy)hexane, di-t-butyldiperoxyisophthalate, 2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane,di-t-butyl peroxy-α-methylsuccinate, di-t-butyl peroxydimethylglutarate,di-t-butyl peroxyhexahydroterephthalate, di-t-butyl peroxyazelate,2,5-dimethyl-2,5-di(t-butylperoxy)hexane, diethylene glycolbis(t-butylperoxycarbonate), di-t-butyl peoxytrimethyladipate,tris(t-butylperoxy)triazine, vinyl tris(t-butylperoxy)silane and thelike. These may be used singly or in combination. As for the amountthereof, they may be used in a concentration of 0.05 mass parts or more,preferably from 0.1 to 15 mass parts per 100 mass parts of the monomer.

<Electrical Charge Controlling Agent>

A commonly used electrical charge controlling agent can be used as anelectrical charge controlling agent that is combined with the binderresin comprising the PHA of the present invention. Specific examples ofsuch an electrical charge controlling agent may include nigrosinedyestuff, quaternary ammonium salts, and monoazo metallic complex saltdyestuff. The additive amount of an electrical charge controlling agentcan be determined, considering various conditions such as theelectrification characteristic of the binder resin, the productionmethod including the additive amount of a coloring agent and adispersion method, and the electrification characteristic of otheradditives. The electrical charge controlling agent can be addedgenerally at a ratio of 0.1 to 20 parts by mass, and preferably at aratio of 0.5 to 10 parts by mass with respect to 100 parts by mass ofbinder resin. Other than the above described substances, inorganicparticles of metallic oxide, or inorganic substances whose surface istreated with the above organic substances, may also be used. Theseelectrical charge controlling agents may be mixed into the binder resin,or may be attached on the surface of toner particles.

<Colorant>

As for the colorant that constitutes the electrostatic charge imagedeveloping toner of the present invention, any colorant that isgenerally used in producing toners may be used and is not particularlylimited. For example, carbon black, titanium white, monoazo redpigments, disazo yellow pigments, quinacridone magenta pigments,anthraquinone pigments, any other pigments and/or dyes may be used.

More concretely speaking, when the electrostatic charge image developingtoner of the present invention is used as a magnetic color toner, thecolorant that can be used includes, for example, C.I. Direct Red 1, C.I.Direct Red. 4, C.I. Acid Red 1, C.I. Basic Red 1, C.I. Mordant Red 30,C.I. Direct Blue 1, C.I. Direct Blue 2, C.I. Acid Blue 9, C.I. Acid Blue15, C.I. Basic Blue 3, C.I. Basic Blue 5, C.I. Mordant Blue 7, C.I.Direct Green 6, C.I. Basic Green 4, C.I. Basic Green 6, etc.

As the pigment, there may be used chrome yellow, cadmium yellow, mineralfast yellow, navel yellow, naphthol yellow S, Hansa yellow G, permanentyellow NCG, tartrazine lake, chrome orange, molybdenum orange, permanentorange GTR, pyrazolone orange, benzidine orange G, cadmium red,permanent red 4R, watching red calcium salt, eosin lake, brilliantcarmine 3B, manganese violet, fast violet B, methyl violet lake,Prussian blue (iron blue), cobalt blue, alkali blue lake, victoria bluelake, phthalocyanine blue, fast sky blue, indanthrene blue BC, chromegreen, chromium oxide, pigment green B, malachite green lake, finalyellow green G and the like.

Further, when the electrostatic charge image developing toner of thepresent invention is used as a toner for two-component full color toner,the following may be used as a colorant. Examples of the coloringpigment for magenta color toner include C.I. Pigment Red 1, 2, 3, 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31,32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63,64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 202, 206, 207,and 209, C.I. Pigment Violet 19, C.I. Vat Red 1, 2, 10, 13, 15, 23, 29,and 35, etc.

In the present invention, the above-cited pigments may be used singly.However, it is more preferred that a dye and a pigment are used incombination to increase sharpness of the pigment in consideration of theimage quality of full color images. Examples of the dye for magenta usedin this case include oil-soluble dyes, such as C.I. Solvent Red 1, 3, 8,23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, and 121, C.I. DisperseRed 9, C.I. Solvent Violet 8, 13, 14, 21, and 27, C.I. Disperse Violet1, etc.; basic dyes, such as C.I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17,18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. BasicViolet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, and 28; etc.

Other coloring pigments include cyan coloring pigments, such as C.I.Pigment Blue 2, 3, 15, 16, and 17, C.I. Vat Blue 6, C.I. Acid Blue 45and copper phthalocyanine pigments having a phthalocyanine skeletonsubstituted with 1 to 5 phthalimidomethyl groups, etc.

Examples of the coloring pigment for yellow include C.I. Pigment Yellow1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, and 83,C.I. Vat Yellow 1, 3, and 20, etc.

The dyes and pigments as described above may be used singly or asoptional mixtures in order to obtain a desired color tone of the toner.Taking into consideration environmental protection or safety for thehuman body, various kinds of edible coloring matter such as edible lakemay be suitably used. Examples of such a food color may include food red40 aluminum lake, food red 2 aluminum lake, food red 3 aluminum lake,food red 106 aluminum lake, food yellow 5 aluminum lake, food yellow 4aluminum lake, food blue 1 aluminum lake, and food blue 2 aluminum lake.

The above water-insoluble food colors can be function as electricalcharge controlling agents. In this case, the above aluminum lake can bepreferably used for negative charge. Thus, when a water-insoluble foodcolor has a function as an electrical charge controlling agent, itcannot only improve the safety of a toner to the environment, but alsocan contribute to the cost-reduction of the toner.

The content of the above-mentioned colorants in the toner may be variedwidely depending on a desired coloring effect or other factors. Usually,to obtain the best toner characteristics, that is, taking intoconsideration coloring power of printing, shape stability of toner,flying of toner and so forth, the colorants are used in a proportion ofusually from 0.1 to 60 mass parts, preferably from 0.5 to 20 mass partsper 100 mass parts of the binder resin.

<Other Components of Toner>

The electrostatic charge image developing toner of the present inventionmay contain, besides the above-mentioned binder resin and colorantcomponents, the compounds described below within the range in which theydo not give adverse influence on the effects of the present invention(in a proportion smaller than the contents of the binder resincomponent). Examples of such compounds include aliphatic or alicyclichydrocarbon resins and aromatic petroleum resins, such as siliconeresin, polyester, polyurethane, polyamide, epoxy resin, polyvinylbutyral, rosin, modified rosin, terpene resin, phenol resin, lowmolecular weight polyethylene, and low molecular weight polyproplene,and chlorinated paraffin, paraffin wax, and so-forth. Preferably usablewaxes among these specifically include low molecular weightpolypropylene and side products thereof, low molecular weight polyestersand ester-based waxes, aliphatic derivatives thereof. Also, waxesprepared by fractionation of these waxes according to molecular weightby various methods may be preferably used in the present invention.Further, after the fractionation, oxidation, block copolymerization orgraft modification may be performed.

In particular, the electrostatic charge image developing toner of thepresent invention exhibits excellent characteristics in the case wherelaminagraphic observation performed with a transmission electronmicroscope (TEM) shows that the wax component is dispersed in the binderresin in the form of substantially spherical and/or spindle-shapedislets

<Toner Production Process>

As a specific method for producing the electrostatic charge imagedeveloping toner of the present invention having the above constitution,any one of known methods may be used. The electrostatic charge imagedeveloping toner of the present invention can be produced by theso-called pulverization method in which a toner is obtained, forexample, by the following processes.

That is, stated specifically, the electrostatic charge image developingtoner of the present invention can be obtained as follows: resins suchas a binder resin, and a electrical charge controlling agent and a waxthat is added as needed are sufficiently mixed in a mixer such as aHenschel mixer, a ball mill or the like and melt-kneaded by using athermal kneader such as a heat roll, a kneader or an extruder to makethe resins compatible with each other. Then, a pigment, dye or magneticmaterial as a colorant, and an additive that is added as needed, such asa metal compound, are dispersed or dissolved in the kneaded resin andcooled and solidified. The solid is then pulverized by a pulverizer suchas a jet mill or a ball mill and classified to produce the electrostaticcharge image developing toner of the present invention having a desiredparticle size. In the classification step, it is preferred to use amultisegment classifier to increase the production efficiency.

The electrostatic charge image developing toner of the present inventioncan be obtained also by the following method. That is, a binder resinand the electrical charge controlling agent are mixed in the form ofsolutions by using a solvent or solvents (aromatic hydrocarbons such astoluene and xylene, halides such as chloroform and ethylene dichloride,ketones such as acetone and methyl ethyl ketone, amides such asdimethylformamide, and the like) and agitated. Thereafter, the mixedsolution is poured into water to cause reprecipitation, and the solidsare filtered, dried and pulverized by using a pulverizer such as a jetmill or a ball mill, followed by classification to obtain theelectrostatic charge image developing toner of the present inventionhaving a desired particle size. In the classification step, it ispreferred to use a multisegment classifier to increase the productionefficiency.

Further, the electrostatic charge image developing toner of the presentinvention can be obtained also by a so-called polymerization method asdescribed below. In this case, the binder resin of the presentinvention, a polymerizable monomer of the other binder resin and aelectrical charge controlling agent and a materials such as a pigment,dye or magnetic material as a colorant and optionally a crosslinkingagent, a polymerization initiator, a wax, the other binder resin andother additives are mixed and dispersed and subjected to suspensionpolymerization in an aqueous dispersion medium in the presence of asurfactant and the like to synthesize polymerizable colored resinparticles. Then, the obtained particles are subjected to solid-liquidseparation, dried and classified as necessary to obtain theelectrostatic charge image developing toner of the present invention.

Furthermore, colored fine particles containing no charge control agentcan be prepared by the methods described above and then, the electricalcharge controlling agent, singly or together with an external additivesuch as colloidal silica, may be added and fixed to the surface of theparticles by a mechanochemical method or the like.

(Silica External Additive)

In the present invention, it is preferred that silica fine powder isadded externally to the toner prepared by the above-mentioned method inorder to increase charge stability, developability, flowability anddurability. On this occasion, use of silica fine powder that has aspecific surface area in the range of 20 m²/g or more, in particular 30to 400 m²/g, as measured by nitrogen absorption according to the BETmethod can give good results. In this case, it is preferred to use thesilica fine powder in an amount of from about 0.01 to about 8 massparts, preferably from about 0.1 to about 5 mass parts, per 100 massparts of the toner particle. As for the silica fine powder to be used,it is preferred to use one that is treated with a treating agent such assilicone varnish, various kinds of modified silicone varnish, siliconeoil, various kinds of modified silicone oil, silane coupling agents,silane coupling agents having a functional groups, and otherorganosilicon compounds as needed for the purpose of imparting to thetoner hydrophobic nature or controlling the chargeability of the toner.These treating agents may be used as mixtures.

(Inorganic Powder)

To increase the developability and durability of the toner, it ispreferred to add inorganic powders, for example, powders of oxides ofmetals such as magnesium, zinc, aluminum, cerium, cobalt, iron,zirconium, chromium, manganese, strontium, tin, and antimony; compositemetal oxides such as calcium titanate, magnesium titanate, and strontiumtitanate; metal salts such as calcium carbonate, magnesium carbonate andaluminum carbonate; clay minerals such as kaolin; phosphate compoundssuch as apatite; silicon compounds such as silicon carbide and siliconnitride; and carbon powders such as carbon black and graphite. Amongthose, fine powders of zinc oxide, aluminum oxide, cobalt oxide,manganese dioxide, strontium titanate, and magnesium titanate arepreferably used.

(Lubricant)

Further, lubricant powder as described below may be added to the toner.Examples of the lubricant powder includes fluororesins such as Teflon,polyvinylidene fluoride; fluoro compounds such as carbon fluoride; fattyacid metal salts such as zinc stearate; fatty acid, fatty acidderivatives such as fatty acid esters; molybdenum sulfide and the like.

Although contents of these colorant, electrical charge controllingagent, binder resin used in mixture with the binder resin of the presentinvention and additives added as occasion demands in the toner areslight, it is more preferable to use any biodegradable material for themin view of waste disposal.

<Carrier>

The electrostatic charge image developing toner of the present inventionhaving the above-described structure and properties may be applied tovarious kinds of known toners; for example, it may be used as anonmagnetic toner that is used singly as a nonmagnetic one-componentdeveloper or as a magnetic two-component developer together with amagnetic carrier, or as a magnetic toner used singly as a magneticone-component developer. Any conventionally known carrier may be used asa carrier in the two-component developing method. Specifically,surface-oxidized or -non-oxidized particles having an average particlesize of from 20 to 300 μm formed from metals such as iron, nickel,cobalt, manganese, chromium, and rare earth elements, alloys thereof oroxides may be used as carrier particles. It is preferred that thecarrier used in the present invention comprise the carrier particlesdescribed above, the surface of which are coated with a substance suchas a styrene-based resin, acrylic-based resin, a silicone-based resin, afluoro-based resin, a polyester resin or the like or has such asubstance adhered thereto.

<Magnetic Toner>

The electrostatic charge image developing toner of the present inventionmay contain a magnetic material in the toner particles to form amagnetic toner. In this case, the magnetic material may also serve as acolorant. The magnetic material that can be used on this occasionincludes iron oxides such as magnetite, hematite and ferrite; and metalssuch as iron, cobalt and nickel or alloys and mixtures of these metalswith other metals such as aluminum, cobalt, copper, lead, magnesium,tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese,selenium, titanium, tungsten, and vanadium. Preferably, the magneticmaterials that can be used in the present invention have an averageparticle size of 2 μm or less, more preferably from about 0.1 to about0.5 μm. It is preferred that they are contained in the toner in anamount of from 20 to 200 mass parts per 100 mass parts of the binderresin, particularly preferably from 40 to 150 mass parts per 100 massparts of the binder resin.

Further, to accomplish high image quality, it is necessary to make itpossible to faithfully develop finer latent image dots. For thispurpose, for example, it is preferable to control the electrostaticcharge image developing toner particles of the present invention so asto have a weight average particle size in the range of from 4 to 9 μm.That is, the toner particles having a weight average particle size lessthan 4 μm are undesirable, since with such a toner the image transferefficiency tends to decrease and much untransferred toner is liable toremain on the photosensitive member after the transfer, which tends tocause unevenness of image due to fogging/transfer failure. If the weightaverage particle size of the toner particle exceeds 9 μm, scattering ofcharacters or line images tends to occur.

In the present invention, the average particle size and particle sizedistribution of the toner are determined by using Coulter Counter TA-II(available from Coulter Electronics, Inc.) or Coulter Multisizer(available from Coulter Electronics Inc.), connected to an interface(Nikkaki Co., Ltd.) for outputting number distribution and volumedistribution, and a personal computer PC 9801 (available from NEC K.K.).As the electrolyte to be used in the measurement is a 1% NaCl aqueoussolution prepared with first class grade sodium chloride. The 1% NaClaqueous solution is also commercially available; for example, ISOTONR-II (produced by Coulter Scientific Japan Co.). Specifically, formeasurement, 0.1 to 5 mL of a surfactant (preferably analkylbenzenesulfonic acid salt) as a dispersant and further 2 to 20 mgof a measurement sample are added to 100 to 150 mL of the electrolyticsolution to form a sample for measurement. In the measurement, theresultant suspension of the measurement sample in the electrolyticsolution is subjected to a dispersion treatment by an ultrasonicdisperser for about 1 to 3 minutes and then subjected to measurement ofparticle size distribution by using the above-mentioned Coulter CounterTA-II equipped with a 100 μm-aperture as an aperture to obtain thevolume and number of toner particles equal to or greater than 2 μm. Fromthese a volume-basis particle size distribution and a number-basisparticle size distribution were calculated. Then, the volume-basisweight average particle size (D4) and number-basis length-averageparticle size (D1) related to the present invention are derived from thevolume-basis and number-basis distributions, respectively.

<Charge Amount>

It is preferred that the electrostatic charge image developing toner ofthe present invention has a charge quantity (two component method) perunit mass methacryloxypolyethoxyphenyl)propane, of −10 to −80 μC/g, morepreferably −15 to −70 μC/g in order to increase transfer efficiency in atransfer method using a voltage applied transfer member.

The method for measuring a charge quantity (two component triboelectriccharge amount) by a two component method used in the present inventionis as indicated below. For measurement, a charge amount measuringapparatus as shown in FIG. 7 is used. First, under a certainenvironment, a mixture of 9.5 g of EFV 200/300 (tradename, produced byPowdertech Co., Ltd.) as a carrier and 0.5 g of toner to be measured isadded into a 50 to 100 mL capacity polyethylene bottle, which is thenplaced in a shaker set under shaking conditions of a fixed shaking widthof 100 mm and a shaking speed of 100 strokes per minute and shaken for apredetermined period of time. Then, 1.0 to 1.2 g of the shaken mixtureis charged in a measurement container 42 (made of metal) provided with a500-mesh screen 43 at the bottom of the charge amount measuringapparatus shown in FIG. 7 and covered with a metal lid 44. The totalmass of the measurement container 42 is weighed and denoted by WI (g).Then, an aspirator (not shown), in which at least the part contactingwith the measurement container 42 is composed of an insulator, isoperated to effect suction through a suction port 47 while pressure isso regulated as to be 2450 Pa (250 mmAq) with a vacuum gauge 45 byadjusting an airflow control valve 46. In this state, suction iscontinued for 1 minute to remove the toner. The reading at this time ofa potential meter 49 is denoted by V (volts). Here, 48 designates acapacitor having a capacitance C (μF). The total mass of the measuringapparatus after the suction is measured and denoted by W2 (g). Then, thetriboelectric charge amount (μC/g) of the toner is calculated by thefollowing equation:Triboelectric charge amount (μC/g)=CxV/(W1-W2).<Molecular Weight Distribution of Binder Resin>

It is preferred that the binder resin used as a constituent material ofthe electrostatic charge image developing toner of the present inventionshows a low molecular weight region peak in the range from 3,000 to15,000 in the molecular weight distribution by gel permeationchromatography (GPC), in particular, when it is prepared by apulverization method. That is, if the GPC peak in the low molecularweight region exceeds 15,000, improvement in transfer efficiency may insome cases become insufficient. On the other hand, the use of a binderresin having a GPC peak in the low molecular weight region of less than3,000 is not desirable since fusion tends to occur at the time ofsurface treatment.

In the present invention, the molecular weight of the binder resin ismeasured by gel permeation chromatography (GPC). A specific method forthe measurement by GPC may include the following method: the toner isbeforehand extracted with THF (tetrahydrofuran) solvent for 20 hours bymeans of a Soxhlet extractor, and the sample thus obtained is used formeasurement of molecular weight by using columns of Shodex A-801, 802,803, 804, 805, 806 and 807, (trade names, made by Showa Denko K.K.)connected in series, and using a calibration curve of referencepolystyrene resin. In the present invention, it is preferred to use abinder resin having a ratio (Mw/Mn), which is a ratio of the weightaverage molecular weight (Mw) and number average molecular weight (Mn)thus measured, in the range of from 2 to 100.

<Glass Transition Point of Toner>

It is preferred that the toner of the present invention is so preparedas to have a glass transition point Tg of 40 to 75° C., more preferably52 to 70° C., by using appropriate materials in consideration of fixingproperty and shelf life. In this case, the glass transition point Tg ofthe toner is measured using a high-precision differential scanningcalorimeter in internal heat, input compensation type, for example,DSC-7, manufactured by Perkin Elmer Co., according to ASTM D3418-82. Inthe present invention, when measuring the glass transition point Tg, thetemperature of a sample to be measured is once elevated to record allthe thermal hysteresis and then quickly cooled. Again, the temperatureof the sample is elevated at a temperature rise rate of 10° C./minutewithin the temperature range of 0 to 200° C. A DSC curve obtained basedon the results of measurements under these conditions may be suitablyused.

<Image Forming Method>

The electrostatic charge image developing toner of the present inventiondescribed above is particularly preferably applied to an image formingmethod comprising at least a charging step of charging an electrostaticlatent image bearing member by applying a voltage to a charging memberfrom the outside, a step of forming an electrostatic charge image on thecharged electrostatic latent image bearing member, a developing step ofdeveloping the electrostatic charge image by using a toner to form atoner image on the electrostatic latent image bearing member, a transferstep of transferring the toner image on the electrostatic latent imagebearing member to a recording medium, and a heat-fixing step ofthermally fixing the toner image on the recording medium thereto.Alternatively, the toner of the present invention may be particularlypreferably applied to the above-described method in which the transferstep comprises a first transfer step of transferring the toner image onthe electrostatic latent image bearing member to an intermediatetransfer member and a second transfer step of transferring the tonerimage on the intermediate transfer member to the recording medium.

It should be noted that the culture of microorganisms, the recovery ofPHA from microorganism cells, resin compositions, molded articles or thelike, and toner binder resins or the like of the present invention arenot limited to those described in the above methods.

EXAMPLES

The present invention will be further described in the followingExamples and Comparative Examples. The Examples are illustrative of thebest mode of the embodiment of the present invention, but the presentinvention is not limited thereto. The number of parts in each of thefollowing compositions represents part by mass, and “%” means apercentage on the basis of mass, unless otherwise specified.

PHA

First, a method for preparing polyhydroxyalkanoate of the presentinvention comprising a microbiological production step and a chemicalprocessing step is shown below (Preparation Examples A-1 to A-4,Comparative Preparation Example A-1, and Examples A-1 to A-8).

Preparation Example A-1

Each 200 ml of an M9 culture medium containing 0.5% of sodium glutamateand 0.1% of 4-(phenylsulfanyl)butyric acid was charged into 24 shakingflasks of 500 ml volume, sterilized under high temperature and highpressure, and cooled to room temperature to prepare a culture medium.

Pseudomonas cichorii YN2 strain was seeded on an M9 culture mediumcontaining 0.5% of polypeptone and shaking-cultured at 30° C. for 8hours to prepare a cell culture solution in advance. Each 2 ml of thisculture solution was added to the above culture medium containing4-(phenylsulfanyl)butyric acid as a matrix to shaking-culture the cellsat 30° C. and 125 strokes/minute. Sixty-four hours later, the cells werecollected by centrifugation, washed with cold methanol once, and thendried under vacuum.

The pellet of this dried cell was suspended in 150 ml of chloroform andstirred at 35° C. for 16 hours to extract PHA. After filtering by amembrane filter of the pore size of 0.45 μm, the extract wasconcentrated by a rotary evaporator. The concentrated solution was addedto cold methanol, and PHA was reprecipitated. Only the precipitate wascollected and dried under vacuum. The resultant PHA was weighed andfound to be 889 mg.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 24,400, andthe weight average molecular weight Mw was 55,100.

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature) The ¹H-NMRspectrum is shown in FIG. 8, and the identified results are shown inTable 1. As a result, the PHA was found to contain 95 mol % of3-hydroxy-4-(phenylsulfanyl)butyric acid shown by chemical formula (22)and total 5 mol % of the others (straight-chained 3-hydroxyalkanoic acidhaving 4 to 12 carbon atoms and 3-hydroxyalk-5-enoic acid having 10 or12 carbon atoms). TABLE 1 (22)

Chemical shift (ppm) Identified result 2.58 b1 3.09 d1 5.27 c1 7.15 h17.26 g1, i1 7.36 f1, j1

Polyhydroxyalkanoate obtained here was utilized in the next reaction.

403 mg of polyhydroxyalkanoate was charged in a 100 ml round bottomedflask, and 10 ml of chloroform was added and dissolved. The flask wasplaced in an ice bath, and methachloroperbenzoic acid in 20 ml ofchloroform was gradually added followed by stirring. After stirring for75 minutes cooling on ice bath, 100 ml of water and 1,000 mg of sodiumbisulfite were added. Then, the mixture was extracted by chloroform tocollect the polymer. Next, the mixture was washed with 2 portions of 100ml of ethanol and dried under a reduced pressure to obtain 377 mg of thepolymer.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8020, column: two PolymerLaboratory PlgelMIXED-C (5 μm); moving phase solvent: DMF containing 0.1wt % of LiBr chloroform; polystyrene equivalent), and hence it was foundthat the number average molecular weight Mn was 14,100, and the weightaverage molecular weight Mw was 39,200.

The structure of the resultant polymer was determined by ¹H-NMR (FT-NMR:Bruker DPX400; resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: DMSO-d₆; reference: capillary-encapsulatedDMSO-d₆; measurement temperature: room temperature). The ¹H-NMR spectrumis shown in FIG. 9, and the identified results are shown in Table 2. Asa result, the PHA was found to contain 98 mol % of3-hydroxy-4-(phenylsulfonyl)butyric acid shown by chemical formula (23)and total 2 mol % of the others (straight-chained 3-hydroxyalkanoic acidhaving 4 to 12 carbon atoms and 3-hydroxyalk-5-enoic acid having 10 or12 carbon atoms).

By scaling up the above preparation method, 50 g of PHA was obtained andit was referred to as PHAA-1. TABLE 2 (23)

Chemical shift (ppm) Identified result 2.32-2.69 b2 3.68 d2 5.31 c2 7.61f2, h2 7.71 g2 7.83 e2, i2

Preparation Example A-2

Each 200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.) and 0.1% of 5-(phenylsulfanyl)valericacid was charged into 24 shaking flasks of 500 ml volume, sterilizedunder high temperature and high pressure, and cooled to room temperatureto prepare a culture medium.

Pseudomonas cichorii YN2 strain was seeded on an M9 culture mediumcontaining 0.5% of polypeptone and shaking-cultured at 30° C. for 8hours to prepare a cell culture solution in advance. Each 2 ml of thisculture solution was added to the above culture medium containing5-(phenylsulfanyl)valeric acid as a matrix to shaking-culture the cellsat 30° C. and 125 strokes/minute. Twenty-four hours later, the cellswere collected by centrifugation, washed with cold methanol once, andthen dried under vacuum.

The pellet of this dried cell was suspended in 200 ml of chloroform andstirred at 35° C. for 17 hours to extract PHA. After filtering by amembrane filter of the pore size of 0.45 μm, the extract wasconcentrated by a rotary evaporator. The concentrated solution was addedto cold methanol, and PHA was reprecipitated. Only the precipitate wascollected and dried under vacuum. The resultant PHA was weighed andfound to be 2,939 mg.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 227,100, andthe weight average molecular weight Mw was 671,300.

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). The ¹H-NMRspectrum is shown in FIG. 10, and the identified results are shown inTable 3. As a result, the PHA was found to contain 94 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid shown by chemical formula (24)and total 6 mol % of the others (straight-chained 3-hydroxyalkanoic acidhaving 4 to 12 carbon atoms and 3-hydroxyalk-5-enoic acid having 10 or12 carbon atoms). TABLE 3 (24)

Chemical shift (ppm) Identified result 1.89 d3 2.42-2.56 b3 2.80-2.90 e35.27 c3 7.13 i3 7.23-7.29 g3, h3, j3, k3

Polyhydroxyalkanoate obtained here was utilized in the next reaction.

400 mg of polyhydroxyalkanoate was charged in a 100 ml round bottomedflask, and 10 ml of chloroform was added and dissolved. The flask wasplaced in an ice bath, and 1386 mg of methachloroperbenzoic acid in 20ml of chloroform was gradually added followed by stirring. Afterstirring for 75 minutes cooling on ice bath, 100 ml of water and 3,020mg of sodium bisulfite were added. Then, the mixture was extracted bychloroform to collect the polymer. Next, the mixture was washed with 2portions of 100 ml of ethanol and dried under a reduced pressure toobtain 373 mg of the polymer.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 107,300, andthe weight average molecular weight Mw was 275,500.

The structure of the resultant polymer was determined by ¹H-NMR (FT-NMR:Bruker DPX400; resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). The ¹H-NMRspectrum is shown in FIG. 11, and the identified results are shown inTable 4. As a result, the PHA was found to contain 91 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid shown by chemical formula (25)and total 9 mol % of the others (straight-chained 3-hydroxyalkanoic acidhaving 4 to 12 carbon atoms and 3-hydroxyalk-5-enoic acid having 10 or12 carbon atoms).

By scaling up the above preparation method, 50 g of PHA was obtained andit was referred to as PHAA-2. TABLE 4 (25)

Chemical shift (ppm) Identified result 1.99 d4 2.47-2.60 b4 3.12-3.16 e45.18 c4 7.51 h4, j4 7.60 i4 7.84 g4, k4

Preparation Example A-3

Polyhydroxyalkanoate obtained here was utilized in the next reaction.

400 mg of polyhydroxyalkanoate was charged in a 100 ml round bottomedflask, and 10 ml of chloroform was added and dissolved. The flask wasplaced in an ice bath, and 463 mg of methachloroperbenzoic acid in 20 mlof chloroform was gradually added followed by stirring. After stirringfor 75 minutes cooling on ice bath, 100 ml of water and 1,000 mg ofsodium bisulfite were added. Then, the mixture was extracted bychloroform to collect the polymer. Next, the mixture was washed with 2portions of 100 ml of ethanol and dried under a reduced pressure toobtain 366 mg of the polymer.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (Tosoh HLC-8020, column: two PolymerLaboratory PlgelMIXED-C (5 μm); moving phase solvent: DMF containing 0.1wt % of LiBr; polystyrene equivalent), and hence it was found that thenumber average molecular weight Mn was 121,300, and the weight averagemolecular weight Mw was 286,500.

The structure of the resultant polymer was determined by ¹H-NMR (FT-NMR:Bruker DPX400; resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). As a result, thePHA was found to contain 63 mol % of 3-hydroxy-5-(phenylsulfinyl)valericacid shown by chemical formula (26), 31 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid shown by chemical formula (25),and total 9 mol % of the others (straight-chained 3-hydroxyalkanoic acidhaving 4 to 12 carbon atoms and 3-hydroxyalk-5-enoic acid having 10 or12 carbon atoms).

By scaling up the above preparation method, 50 g of PHA was obtained andit was referred to as PHAA-3.

Preparation Example A-4

Each 200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 0.1% of 5-(phenylsulfanyl)valeric acid,and 1.0 mM of 5-phenylvaleric acid was charged into 8 shaking flasks of500 ml volume, sterilized under high temperature and high pressure,cooled, and seeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Forty-four hourslater, the cells were collected by centrifugation, washed with coldmethanol once, and then dried under vacuum.

The pellet of this dried cell was suspended in 100 ml of chloroform andstirred at 35° C. for 16 hours to extract PHA. After filtering by amembrane filter of the pore size of 0.45 μm, the extract wasconcentrated by a rotary evaporator. The concentrated solution was addedto cold methanol, and PHA was reprecipitated. Only the precipitate wascollected and dried under vacuum. The resultant PHA was weighed andfound to be 929 mg.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 141,200, andthe weight average molecular weight Mw was 393,800.

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature) The ¹H-NMRspectrum is shown in FIG. 12 and the identified results are shown inTable 5. As a result, the polyhydroxyalkanoate copolymer was found tocontain 73 mol % of 3-hydroxy-5-(phenylsulfanyl)valeric acid shown bychemical formula (27), 21 mol % of 3-hydroxy-5-phenylvaleric acid shownby chemical formula (28), and total 6 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms). TABLE 5 (27)

(28)

Chemical shift (ppm) Identified result 1.88 d5, d6 2.39-2.57 b5, b6, e62.78-2.88 e5 5.18-5.27 c5, c6 7.13 i5, g6, i6, k6 7.24 g5, h5, j5, k5,h6, j6

851 mg of a polyhydroxyalkanoate copolymer containing 73 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 21 mol % of3-hydroxy-5-phenylvaleric acid, and total 6 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms) as monomer unitswas added to a 300 ml round bottomed flask, and then 60 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 9 ml of acetic acid and 2,537 mg of 18-crown-6-ether wereadded followed by stirring. Next, 2,020 mg of potassium permanganate wasgradually added in an ice bath, followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 6,030mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0N hydrochloric acid. After dichloromethane in the mixedsolution was distilled off by an evaporator, the polymer in the solutionwas collected. The polymer was washed with 100 ml of methanol, and thenthree portions of 100 ml of pure water followed by collecting thepolymer. The thus obtained polymer was purified by dialysis by usingchloroform. After purification, 1,137 mg of the desired PHA was obtainedby drying under a reduced pressure.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 42,800, andthe weight average molecular weight Mw was 112,200.

In order to determine the construction of the resultant PHA, analysiswas performed by ¹H-NMR (FT-NMR: Bruker DPX400; resonance frequency: 400MHz; measurement nuclear species: ¹H; solvent used: CDCl₃; reference:capillary-encapsulated TMS/CDCl₃; measurement temperature: roomtemperature). The ¹H-NMR spectrum is shown in FIG. 13, and theidentified results are shown in Table 6. As a result, the PHA was foundto be a polyhydroxyaikanoate copolymer containing 71 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid shown by chemical formula (29),23 mol % of 3-hydroxy-5-phenylvaleric acid shown by chemical formula(30), and total 6 mol % of the others (straight-chained3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms).

By scaling up the above preparation method, 50 g of PHA was obtained andit was referred to as PHAA-4. TABLE 6 (29)

(30)

Chemical shift (ppm) Identified result 1.88 d8 2.00 d7 2.54 b8, e8, b73.15 e7 5.18 c8, c7 7.13 g8, i8, k8 7.24 h8, j8 7.51 h7, j7 7.58 i7 7.86g7, k7

Comparative Preparation Example A-1

200 ml of an M9 culture medium containing 0.5% of a yeast extract (fromOriental Yeast Co., Ltd.) was seeded with Pseudomonas cichorii H45strain and shaking-cultured at 30° C. and 125 strokes/minute for 8 hoursto prepare a spawn. 25 L of an M9 culture medium containing 0.1% of5-phenylvaleric acid and 0.5% of D-glucose was prepared-in a 50 L jarfermenter, and the spawn was charged thereto and cultured with aerationand stirring at 30° C., 70 rpm, and 9.4 L/minute of an aeration amount.After 48 hours, the cells were collected by centrifugation, resuspendedin 25 L of an M9 culture medium containing 0.1% of 5-phenylvaleric acidand 0.5% of D-glucose and not containing a nitrogen source (NH₄Cl), andfurther cultured with aeration and stirring at 30° C., 70 rpm, and 9.4L/minute of an aeration amount. After 48 hours, the cells were collectedby centrifugation, washed once with cold methanol, and lyophilized.

The lyophilized pellets were suspended in 200 ml of chloroform, stirredat 60° C. for 20 hours, and extracted. After filtered by a membranefilter of the pore size of 0.45 μm, the extract was concentrated by arotary evaporator. The concentrated solution was reprecipitated in coldmethanol, and only the precipitate was collected and dried under vacuumto obtain 15.0 g of a resin composition.

A portion of the resin composition was taken, subjected to methanolysisin the usual manner and then analyzed by a Gas Chromatography-MassSpectrometer (GC-MS, Shimadzu QP-5050, EI method) to identify themethylesterified product of the monomer unit composing the resincomposition. As a result, the resin composition was found to becomprised of PHA containing a 3-hydroxy-5-phenylvaleric acid unit only.

By scaling up the above preparation method, 50 g of PHA was obtained andit was referred to as PHAA-5.

Example A-1

Each 200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 0.1% of 5-(phenylsulfanyl)valeric acid,and 1.0 mmol of 5-phenylvaleric acid was charged into 8 shaking flasksof 500 ml volume, sterilized under high temperature and high pressure,cooled, and seeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Forty-four hourslater, the cells were collected by centrifugation, washed with coldmethanol once, and then dried under vacuum.

The pellet of this dried cell was suspended in 100 ml of chloroform andstirred at 35° C. for 16 hours to extract PHA. After filtering by amembrane filter of the pore size of 0.45 μm, the extract wasconcentrated by a rotary evaporator. The concentrated solution was addedto cold methanol, and PHA was reprecipitated. Only the precipitate wascollected and dried under vacuum. The resultant PHA was weighed andfound to be 929 mg.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 141,200, andthe weight average molecular weight Mw was 393,800.

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). The ¹H-NMRspectrum is shown in FIG. 14 and the identified results are shown inTable 7. As a result, the polyhydroxyalkanoate copolymer was found tocontain 73 mol % of 3-hydroxy-5-(phenylsulfanyl)valeric acid, 21 mol %of 3-hydroxy-5-phenylvaleric acid, and total 6 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (31). TABLE 7

(31)

Chemical shift (ppm) Scission Identified result 1.88 br d1, d2 2.39-2.57m b1, b2, e2 2.78-2.88 m e1 5.18-5.27 m c1, c2 7.13 m i1, g2, i2, k27.24 m g1, h1, j1, k1, h2, j2

Example A-2

851 mg of a polyhydroxyalkanoate copolymer containing 73 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 21 mol % of3-hydroxy-5-phenylvaleric acid, and total 6 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms) as monomer unitswas added to a 300 ml round bottomed flask, and then 60 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 9 ml of acetic acid and 2,537 mg of 18-crown-6-ether wereadded followed by stirring. Next, 2,020 mg of potassium permanganate wasgradually added in an ice bath followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 6,030mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane inthe mixed solution was distilled off by an evaporator, the polymer inthe solution was collected. The polymer was washed with 100 ml ofmethanol, and then three portions of 100 ml of pure water followed bycollecting the polymer. 1,137 mg of the desired PHA was obtained bydrying under a reduced pressure.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 42,800, andthe weight average molecular weight Mw was 112,200.

In order to determine the construction of the resultant PHA, analysiswas performed by ¹H-NMR (FT-NMR: Bruker DPX400; ¹H resonance frequency:400 MHz; measurement nuclear species: ¹H; solvent used: CDCl₃;reference: capillary-encapsulated TMS/CDCl₃; measurement temperature:room temperature). The ¹H-NMR spectrum is shown in FIG. 15, and theidentified results are shown in Table 8. As a result, the PHA was foundto be a polyhydroxyalkanoate copolymer containing 71 mol % of3-hydrbxy-5-(phenylsulfonyl)valeric acid, 23 mol % of3-hydroxy-5-phenylvaleric acid, and total 6 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula TABLE 8

(32)

Chemical shift (ppm) Scission Identified result 1.88 br d2 2.00 br d32.54 br b2, e2, b3 3.15 br e3 5.18 br c2, c3 7.13 m g2, 12, k2 7.24 mh2, j2 7.51 br h3, j3 7.58 m i3 7.86 m g3, k3

Example A-3

Each 200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 0.1% of 5-(phenylsulfanyl)valeric acid,and 1.5 mmol of 5-phenylvaleric acid was charged into 8 shaking flasksof 500 ml volume, sterilized under high temperature and high pressure,cooled, and seeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Thirty-nine hourslater, the cells were collected by centrifugation, washed with coldmethanol once, and then dried under vacuum.

The pellet of this dried cell was suspended in 100 ml of chloroform andstirred at 35° C. for 97 hours to extract PHA. After filtering by amembrane filter of the pore size of 0.45 μm, the extract wasconcentrated by a rotary evaporator. The concentrated solution was addedto cold methanol, and PHA was reprecipitated. Only the precipitate wascollected and dried under vacuum. The resultant PHA was weighed andfound to be 1,081 mg.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 232,200, andthe weight average molecular weight Mw was 554,000.

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). The ¹H-NMRspectrum is shown in FIG. 16. As a result, the polyhydroxyalkanoatecopolymer was found to contain 66 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 29 mol % of3-hydroxy-5-phenylvaleric acid, and total 5 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (33).

Example A-4

850 mg of a polyhydroxyalkanoate copolymer containing 66 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 29 mol % of3-hydroxy-5-phenylvaleric acid, and total 5 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms) as monomer unitswas added to a 300 ml round bottomed flask, and then 60 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 9 ml of acetic acid and 2,306 mg of 18-crown-6-ether wereadded followed by stirring. Next, 1,839 mg of potassium permanganate wasgradually added in an ice bath followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 3,000mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane inthe mixed solution was distilled off by an evaporator, the polymer inthe solution was collected. The polymer was washed with 100 ml ofmethanol, and then three portions of 100 ml of pure water followed bycollecting the polymer. The thus obtained polymer was purified bydialysis using chloroform. After purification, 929 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was73,400, and the weight average molecular weight Mw was 195,000.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). The ¹H-NMR spectrum is shownin FIG. 17. As a result, the polyhydroxyalkanoate copolymer was found tocontain 66 mol % of 3-hydroxy-5-(phenylsulfonyl)valeric acid, 30 mol %of 3-hydroxy-5-phenylvaleric acid, and total 4 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (34).

Example A-5

Each 200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 0.1% of 5-(phenylsulfanyl)valeric acid,and 2.0 mmol of 5-phenylvaleric acid was charged into 8 shaking flasksof 500 ml volume, sterilized under high temperature and high pressure,cooled, and seeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Thirty-nine hourslater, the cells were collected by centrifugation, washed with coldmethanol once, and then dried under vacuum.

The pellet of this dried cell was suspended in 100 ml of chloroform andstirred at 35° C. for 97 hours to extract PHA. After filtering by amembrane filter of the pore size of 0.45 μm, the extract wasconcentrated by a rotary evaporator. The concentrated solution was addedto cold methanol, and PHA was reprecipitated. Only the precipitate wascollected and dried under vacuum. The resultant PHA was weighed andfound to be 1,174 mg.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 242,500, andthe weight average molecular weight Mw was 615,500.

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). The ¹H-NMRspectrum is shown in FIG. 18. As a result, the polyhydroxyalkanoatecopolymer was found to contain 60 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 34 mol % of3-hydroxy-5-phenylvaleric acid, and total 6 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (35).

Example A-6

850 mg of a polyhydroxyalkanoate copolymer containing 60 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 34 mol % of3-hydroxy-5-phenylvaleric acid, and total 6 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms) as monomer unitswas added to a 300 ml round bottomed flask, and then 60 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 9.0 ml of acetic acid and 2,127 mg of 18-crown-6-etherwere added followed by stirring. Next, 1,696 mg of potassiumpermanganate was gradually added in an ice bath followed by stirring atroom temperature for 20 hours. After the reaction was completed, 50 mlof water and 3,000 mg of sodium bisulfite were added. Then, the solutionwas made to be pH 1 by adding 1.0 mol/L (1.0N) hydrochloric acid. Afterdichloromethane in the mixed solution was distilled off by anevaporator, the polymer in the solution was collected. The polymer waswashed with 100 ml of methanol, and then three portions of 100 ml ofpure water followed by collecting the polymer. The thus obtained polymerwas purified by dialysis using chloroform. After purification, 951 mg ofthe desired polyhydroxyalkanoate was obtained by drying under a reducedpressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was73,400, and the weight average molecular weight Mw was 194,000.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). The ¹H-NMR spectrum is shownin FIG. 19. As a result, the polyhydroxyalkanoate copolymer was found tocontain 66 mol % of 3-hydroxy-5-(phenylsulfonyl)valeric acid, 30 mol %of 3-hydroxy-5-phenylvaleric acid, and total 4 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (36).

Example A-7

Each 200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 0.1% of 5-(phenylsulfanyl)valeric acid,and 6.0 mmol of 5-phenylvaleric acid was charged into 8 shaking flasksof 500 ml volume, sterilized under high temperature and high pressure,cooled, and seeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Forty-seven hourslater, the cells were collected by centrifugation, washed with coldmethanol once, and then dried under vacuum.

The pellet of this dried cell was suspended in 100 ml of chloroform andstirred at 35° C. for 97 hours to extract PHA. After filtering by amembrane filter of the pore size of 0.45 μm, the extract wasconcentrated by a rotary evaporator. The concentrated solution was addedto cold methanol, and PHA was reprecipitated. Only the precipitate wascollected and dried under vacuum. The resultant PHA was weighed andfound to be 633 mg.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent), and hence itwas found that the number average molecular weight Mn was 84,000, andthe weight average molecular weight Mw was 248,800.

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). The ¹H-NMRspectrum is shown in FIG. 20. As a result, the polyhydroxyalkanoatecopolymer was found to contain 38 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 60 mol % of3-hydroxy-5-phenylvaleric acid, and total 2 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (37).

Example A-8

505 mg of a polyhydroxyalkanoate copolymer containing 38 mol % of3-hydroxy-5-(phenylsulfanyl)valeric acid, 60 mol % of3-hydroxy-5-phenylvaleric acid, and total 3 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms) as monomer unitswas added to a 300 ml round bottomed flask, and then 30 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 4 ml of acetic acid and 779 mg of 18-crown-6-ether wereadded followed by stirring. Next, 618 mg of potassium permanganate wasgradually added in an ice bath followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 1,500mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane inthe mixed solution was distilled off by an evaporator, the polymer inthe solution was collected. The polymer was washed with 100 ml ofmethanol, and then three portions of 100 ml of pure water followed bycollecting the polymer. The thus obtained polymer was purified bydialysis using chloroform. After purification, 550 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was36,200, and the weight average molecular weight Mw was 82,500.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). The ¹H-NMR spectrum is shownin FIG. 21. As a result, the polyhydroxyalkanoate copolymer was found tocontain 37 mol % of 3-hydroxy-5-(phenylsulfonyl)valeric acid, 62 mol %of 3-hydroxy-5-phenylvaleric acid, and total 1 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (38).

Example A-9

1,000 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 1 mM of 5-(phenylsulfanyl)valeric acid,and 6 mM of 5-phenoxyvaleric acid was charged into a 2,000 ml shakingflask, sterilized under high temperature and high pressure, cooled, andseeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 100 strokes/minute. Forty hours later,the cells were collected by centrifugation, washed with cold methanolonce, and then dried under vacuum.

The pellet of this dried cell was suspended in chloroform and stirred at35° C. for 16 hours to extract PHA. After filtering by a membrane filterof the pore size of 0.45 μm, the extract was concentrated by a rotaryevaporator. The concentrated solution was added to cold methanol, andPHA was reprecipitated. Only the precipitate was collected and driedunder vacuum. The resultant PHA was weighed.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent).

The dry weight of cells obtained in the above step, the dry weight ofthe collected polymer, the weight ratio of the collected polymer todried cells, and the number average molecular weight, the weight averagemolecular weight, and the molecular weight distribution of the resultantpolymer are shown together in Table 9. TABLE 9 CDW PDW P/C Mn Mw (mg/L)(mg/L) (%) (×10⁴) (×10⁴) Mw/Mn 650 190 29.2 5.8 13.0 2.2CDW: dry weight of cellsPDW: dry weight of polymerP/C: dry weight of polymer/dry weight of cellsMn: number average molecular weightMw: weight average molecular weightMw/Mn: molecular weight distribution(The definitions of the above CDW, PDW, P/C, Mn, Mw, and Mw/Mn are thesame also in the following tables.)

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 25 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 69 mol % of a3-hydroxy-5-phenoxyvaleric acid unit, and total 6 mol % of the others (astraight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbon atomsand a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms, notshown in the following chemical formula), as shown by chemical formula(39).

This step was carried out for 3 batches, and the resultantpolyhydroxyalkanoate copolymer was used in the next Example.

Example A-10

505 mg of a polyhydroxyalkanoate copolymer containing 25 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 69 mol % of a3-hydroxy-5-phenoxyvaleric acid unit, and total 6 mol % of the others (astraight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbon atomsand a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms) asmonomer units was added to a 300 ml round bottomed flask, and then 30 mlof dichloromethane was added and dissolved. The mixture was placed in anice bath, and 4 ml of acetic acid and 779 mg of 18-crown-6-ether wereadded followed by stirring. Next, 618 mg of potassium permanganate wasgradually added in an ice bath followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 1,500mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane inthe mixed solution was distilled off by an evaporator, the polymer inthe solution was collected. The polymer was washed with 100 ml ofmethanol, and then three portions of 100 ml of pure water followed bycollecting the polymer. The thus obtained polymer was purified bydialysis using chloroform. After purification, 525 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was23,500, and the weight average molecular weight Mw was 50,500.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 27 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid, 69 mol % of3-hydroxy-5-phenylvaleric acid, and total 4 mol % of the others(straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbon atoms and3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), as shown bychemical formula (40).

Example A-11

1,000 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 1.28 g of 5-(phenylsulfanyl)valericacid, and 0.21 g of 5-(4-vinylphenyl)valeric acid was charged into a2,000 ml shaking flask, sterilized under high temperature and highpressure, cooled, and seeded with Pseudomonas cichorii YN2 strain. Thecells were shaking-cultured at 30° C. and 100 strokes/minute.Thirty-eight hours later, the cells were collected by centrifugation,washed with cold methanol once, and then dried under vacuum.

The pellet of this dried cell was suspended in chloroform and stirred at35° C. for 17 hours to extract PHA. After filtering by a membrane filterof the pore size of 0.45 μm, the extract was concentrated by a rotaryevaporator. The solution was redissolved in acetone, and the undissolvedportion was filtered off. Then, after the filtrate was concentrated by arotary evaporator, the concentrated solution was added to cold methanol,and PHA was reprecipitated. Only the precipitate was collected and driedunder vacuum. The resultant PHA was weighed.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent).

The dry weight of cells obtained in the above step, the dry weight ofthe collected polymer, the weight ratio of the collected polymer todried cells, and the number average molecular weight, the weight averagemolecular weight, and the molecular weight distribution of the resultantpolymer are shown together in Table 10. TABLE 10 CDW PDW P/C Mn Mw(mg/L) (mg/L) (%) (×10⁴) (×10⁴) Mw/Mn 917 369 40.2 4.8 12.3 2.5

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 70 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 20 mol % of a3-hydroxy-5-(4-vinylphenyl)valeric acid unit, and total 10 mol % of theothers (a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12carbon atoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbonatoms, not shown in the following chemical formula), as shown bychemical formula (41).

This step was carried out for 2 batches, and the resultantpolyhydroxyalkanoate copolymer was used in the next Example.

Example A-12

505 mg of a polyhydroxyalkanoate copolymer containing 70 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 20 mol % of a3-hydroxy-5-(4-vinylphenyl)valeric acid unit, and total 10 mol % of theothers (a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12carbon atoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbonatoms, not shown in the following chemical formula) as monomer units wasadded to a 300 ml round bottomed flask, and then 30 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 4 ml of acetic acid and 779 mg of 18-crown-6-ether wereadded followed by stirring. Next, 618 mg of potassium permanganate wasgradually added in an ice bath followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 1,500mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane inthe mixed solution was distilled off by an evaporator, the polymer inthe solution was collected. The polymer was washed with 100 ml ofmethanol, and then three portions of 100 ml of pure water followed bycollecting the polymer. The thus obtained polymer was purified bydialysis using chloroform. After purification, 590 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was22,300, and the weight average molecular weight Mw was 45,000.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 71 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid, 21 mol % of3-hydroxy-5-(4-carboxyphenyl)valeric acid, and total 8 mol % of theothers (straight-chained 3-hydroxyalkanoic acid having 4 to 12 carbonatoms and 3-hydroxyalk-5-enoic acid having 10 or 12 carbon atoms), asshown by chemical formula (42).

Example A-13

200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 1 mM of 5-(phenylsulfanyl)valeric acid,and 6 mM of 4-cyclohexylbutyric acid was charged into a 500 ml shakingflask, sterilized under high temperature and high pressure, cooled, andseeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Forty hours later,the cells were collected by centrifugation, washed with cold methanolonce, and then dried under vacuum.

The pellet of this dried cell was suspended in chloroform and stirred at35° C. for 16 hours to extract PHA. After filtering by a membrane filterof the pore size of 0.45 μm, the extract was concentrated by a rotaryevaporator. The concentrated solution was added to cold methanol, andPHA was reprecipitated. Only the precipitate was collected and driedunder vacuum. The resultant PHA was weighed.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent).

The dry weight of cells obtained in the above step, the dry weight ofthe collected polymer, the weight ratio of the collected polymer todried cells, and the number average molecular weight, the weight averagemolecular weight, and the molecular weight distribution of the resultantpolymer are shown together in Table 11. TABLE 11 CDW PDW P/C Mn Mw(mg/L) (mg/L) (%) (×10⁴) (×10⁴) Mw/Mn 790 210 26.6 5.5 12.8 2.3

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDC1₃; measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 66 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, and total 34 mol % of a3-hydroxy-4-cyclohexylbutyric acid unit and the others (astraight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbon atomsand a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms, notshown in the following chemical formula), as shown by chemical formula(43).

This step was carried out for 3 batches, and the resultantpolyhydroxyalkanoate copolymer was used in the next Example.

Example A-14

505 mg of a polyhydroxyalkanoate copolymer containing 66 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, a3-hydroxy-4-cyclohexylbutyric acid unit, and total 34 mol % of theothers (a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12carbon atoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbonatoms, not shown in the following chemical formula) as monomer units wasadded to a 300 ml round bottomed flask, and then 30 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 4 ml of acetic acid and 779 mg of 18-crown-6-ether wereadded followed by stirring. Next, 618 mg of potassium permanganate wasgradually added in an ice bath followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 1,500mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane inthe mixed solution was distilled off by an evaporator, the polymer inthe solution was collected. The polymer was washed with 100 ml ofmethanol, and then three portions of 100 ml of pure water followed bycollecting the polymer. The thus obtained polymer was purified bydialysis using chloroform. After purification, 545 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was27,000, and the weight average molecular weight Mw was 62,000.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 68 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid, and total 32 mol % of a3-hydroxy-4-cyclohexylbutyric acid unit and the others (astraight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbon atomsand a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms, notshown in the following chemical formula), as shown by chemical formula(44).

Example A-15

200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 1 mM of 5-(phenylsulfanyl)valeric acid,and 6 mM of 5-benzoylvaleric acid was charged into a 500 ml shakingflask, sterilized under high temperature and high pressure, cooled, andseeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Forty hours later,the cells were collected by centrifugation, washed with cold methanolonce, and then dried under vacuum.

The pellet of this dried cell was suspended in chloroform and stirred at35° C. for 16 hours to extract PHA. After filtering by a membrane filterof the pore size of 0.45 μm, the extract was concentrated by a rotaryevaporator. The concentrated solution was added to cold methanol, andPHA was reprecipitated. Only the precipitate was collected and driedunder vacuum. The resultant PHA was weighed.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent).

The dry weight of cells obtained in the above step, the dry weight ofthe collected polymer, the weight ratio of the collected polymer todried cells, and the number average molecular weight, the weight averagemolecular weight, and the molecular weight distribution of the resultantpolymer are shown together in Table 12. TABLE 12 CDW PDW P/C Mn Mw(mg/L) (mg/L) (%) (×10⁴) (×10⁴) Mw/Mn 750 200 26.7 10.8 34.5 3.2

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 28 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 53 mol % of a3-hydroxy-5-benzoylvaleric acid unit, and total 19 mol % of the others(a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbonatoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms,not shown in the following chemical formula), as shown by chemicalformula (45).

This step was carried out for 3 batches, and the resultantpolyhydroxyalkanoate copolymer was used in the next Example.

Example A-16

505 mg of a polyhydroxyalkanoate copolymer containing 28 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 53 mol % of a3-hydroxy-5-benzoylvaleric acid unit, and total 19 mol % of the others(a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbonatoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms,not shown in the following chemical formula) as monomer units was addedto a 300 ml round bottomed flask, and then 30 ml of dichloromethane wasadded and dissolved. The mixture was placed in an ice bath, and 4 ml ofacetic acid and 779 mg of 18-crown-6-ether were added followed bystirring. Next, 618 mg of potassium permanganate was gradually added inan ice bath followed by stirring at room temperature for 20 hours. Afterthe reaction was completed, 50 ml of water and 1,500 mg of sodiumbisulfite were added. Then, the solution was made to be pH 1 by adding1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane in the mixedsolution was distilled off by an evaporator, the polymer in the solutionwas collected. The polymer was washed with 100 ml of methanol, and thenthree portions of 100 ml of pure water followed by collecting thepolymer. The thus obtained polymer was purified by dialysis usingchloroform. After purification, 515 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was41,000, and the weight average molecular weight Mw was 115,000.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 30 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid, 54 mol % of a3-hydroxy-5-benzoylvaleric acid unit, and total 16 mol % of the others(a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbonatoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms,not shown in the following chemical formula), as shown by chemicalformula (46).

Example A-17

200 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 1 mM of 5-(phenylsulfanyl)valeric acid,and 6 mM of 5-(2-thienyl)valeric acid was charged into a 500 ml shakingflask, sterilized under high temperature and high pressure, cooled, andseeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 125 strokes/minute. Forty hours later,the cells were collected by centrifugation, washed with cold methanolonce, and then dried under vacuum.

The pellet of this dried cell was suspended in chloroform and stirred at35° C. for 16 hours to extract PHA. After filtering by a membrane filterof the pore size of 0.45 μm, the extract was concentrated by a rotaryevaporator. The concentrated solution was added to cold methanol, andPHA was reprecipitated. Only the precipitate was collected and driedunder vacuum. The resultant PHA was weighed.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent).

The dry weight of cells obtained in the above step, the dry weight ofthe collected polymer, the weight ratio of the collected polymer todried cells, and the number average molecular weight, the weight averagemolecular weight, and the molecular weight distribution of the resultantpolymer are shown together in Table 13. TABLE 13 CDW PDW P/C Mn Mw(mg/L) (mg/L) (%) (×10⁴) (×10⁴) Mw/Mn 1,100 540 49.1 8.0 19.6 2.5

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 16 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 80 mol % of a3-hydroxy-5-(2-thienyl)valeric acid unit, and total 4 mol % of theothers (a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12carbon atoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbonatoms, not shown in the following chemical formula), as shown bychemical formula (47).

Example A-18

505 mg of a polyhydroxyalkanoate copolymer containing 16 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 80 mol % of a3-hydroxy-5-(2-thienyl)valeric acid unit, and total 4 mol % of theothers (a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12carbon atoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbonatoms, not shown in the following chemical formula) as monomer units wasadded to a 300 ml round bottomed flask, and then 30 ml ofdichloromethane was added and dissolved. The mixture was placed in anice bath, and 4 ml of acetic acid and 779 mg of 18-crown-6-ether wereadded followed by stirring. Next, 618 mg of potassium permanganate wasgradually added in an ice bath followed by stirring at room temperaturefor 20 hours. After the reaction was completed, 50 ml of water and 1,500mg of sodium bisulfite were added. Then, the solution was made to be pH1 by adding 1.0 mol/L (1.0N) hydrochloric acid. After dichloromethane inthe mixed solution was distilled off by an evaporator, the polymer inthe solution was collected. The polymer was washed with 100 ml ofmethanol, and then three portions of 100 ml of pure water followed bycollecting the polymer. The thus obtained polymer was purified bydialysis using chloroform. After purification, 520 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was37,300, and the weight average molecular weight Mw was 78,500.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 15 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid, 82 mol % of a3-hydroxy-5-(2-thienyl)valeric acid unit, and total 3 mol % of theothers (a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12carbon atoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbonatoms, not shown in the following chemical formula), as shown bychemical formula (48).

Example A-19

1,000 ml of an M9 culture medium containing 0.5% of polypeptone (fromNIHON PHARMACEUTICAL CO., LTD.), 1.0 g of 5-(phenylsulfanyl)valericacid, and 2 mM of 10-undecenoic acid was charged into a 2,000 ml shakingflask, sterilized under high temperature and high pressure, cooled, andseeded with Pseudomonas cichorii YN2 strain. The cells wereshaking-cultured at 30° C. and 100 strokes/minute. Thirty-eight hourslater, the cells were collected by centrifugation, washed with coldmethanol once, and then dried under vacuum.

The pellet of this dried cell was suspended in chloroform and stirred at35° C. for 25 hours to extract PHA. After filtering by a membrane filterof the pore size of 0.45 μm, the extract was concentrated by a rotaryevaporator. The concentrated solution was added to cold methanol, andPHA was reprecipitated. Only the precipitate was collected and driedunder vacuum. The resultant PHA was weighed.

The average molecular weight of the resultant PHA was evaluated by gelpermeation chromatography (GPC; Tosoh HLC-8220, column: Tosoh TSK-GELSuperHM-H; solvent; chloroform; polystyrene equivalent).

The dry weight of cells obtained in the above step, the dry weight ofthe collected polymer, the weight ratio of the collected polymer todried cells, and the number average molecular weight, the weight averagemolecular weight, and the molecular weight distribution of the resultantpolymer are shown together in Table 14. TABLE 14 CDW PDW P/C Mn Mw(mg/L) (mg/L) (%) (×10⁴) (×10⁴) Mw/Mn 1,410 640 45.4 15.0 43.0 2.9

The structure of the resultant PHA was determined by ¹H-NMR (FT-NMR:Bruker DPX400; ¹H resonance frequency: 400 MHz; measurement nuclearspecies: ¹H; solvent used: CDCl₃; reference: capillary-encapsulatedTMS/CDCl₃; measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 78 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 19 mol % of astraight-chained 3-hydroxyalkenoic acid unit with an unsaturatedterminal, and total 3 mol % of the others (a straight-chained3-hydroxyalkanoic acid unit having 4 to 12 carbon atoms and a3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms, not shownin the following chemical formula), as shown by chemical formula (49).

Example A-20

505 mg of a polyhydroxyalkanoate copolymer containing 78 mol % of a3-hydroxy-5-(phenylsulfanyl)valeric acid unit, 19 mol % of astraight-chained 3-hydroxyalkenoic acid unit with an unsaturatedterminal, and total 3 mol % of the others (a straight-chained3-hydroxyalkanoic acid unit having 4 to 12 carbon atoms and a3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms, not shownin the following chemical formula) as monomer units was added to a 300ml round bottomed flask, and then 30 ml of dichloromethane was added anddissolved. The mixture was placed in an ice bath, and 4 ml of aceticacid and 779 mg of 18-crown-6-ether were added followed by stirring.Next, 618 mg of potassium permanganate was gradually added in an icebath followed by stirring at room temperature for 20 hours. After thereaction was completed, 50 ml of water and 1,500 mg of sodium bisulfitewere added. Then, the solution was made to be pH 1 by adding 1.0 mol/L(1.0N) hydrochloric acid. After dichloromethane in the mixed solutionwas distilled off by an evaporator, the polymer in the solution wascollected. The polymer was washed with 100 ml of methanol, and thenthree portions of 100 ml of pure water followed by collecting thepolymer. The thus obtained polymer was purified by dialysis usingchloroform. After purification, 585 mg of the desiredpolyhydroxyalkanoate was obtained by drying under a reduced pressure.

The average molecular weight of the resultant polyhydroxyalkanoate wasevaluated by gel permeation chromatography (GPC; Tosoh HLC-8220, column:Tosoh TSK-GEL SuperHM-H; solvent; chloroform; polystyrene equivalent),and hence it was found that the number average molecular weight Mn was63,500, and the weight average molecular weight Mw was 163,000.

In order to determine the construction of the resultantpolyhydroxyalkanoate, analysis was performed by ¹H-NMR (FT-NMR: BrukerDPX400; ¹H resonance frequency: 400 MHz; measurement nuclear species:¹H; solvent used: CDCl₃; reference: capillary-encapsulated TMS/CDCl₃;measurement temperature: room temperature). As a result, thepolyhydroxyalkanoate copolymer was found to contain 77 mol % of3-hydroxy-5-(phenylsulfonyl)valeric acid, 21 mol % of a3-hydroxy-o-carboxyalkanoic acid unit, and total 2 mol % of the others(a straight-chained 3-hydroxyalkanoic acid unit having 4 to 12 carbonatoms and a 3-hydroxyalk-5-enoic acid unit having 10 or 12 carbon atoms,not shown in the following chemical formula), as shown by chemicalformula (50).

Molded Product of Resin Composition

PHAA-1 to PHAA-5 of the above Preparation Examples A-1 to A-4 andComparative Preparation Example A-1, or a resin composition containingthereof were molded to evaluate degradability and performance as amolded article as follows (Examples B-1 to B-4, Comparative Examples B-1and B-2).

Example B-1

Foamed extruded sheets were molded by using resin compositions PHAA-1 toPHAA-4 described in Preparation Examples A-1 to A-4 and subjected to asecond molding to produce instant noodle containers 1 to 4. Meanwhile,the resin compositions PHAA-1 to PHAA-4 described in PreparationExamples A-1 to A-4 and a polystyrene polymer (Styron 685, from AsahiKasei Corporation) were blended in a mass ratio of 75:25 to produceinstant noodle containers 5 to 8 in the same manner. They were alsoblended in a mass ratio of 51:49 in the same manner to produce instantnoodle containers 9 to 12 in the same manner. Each mass was 3.0 g percontainer.

Comparative Example B-1

A foamed extruded sheet was molded by using the resin composition PHAA-5described in Comparative Preparation Example A-1 and subjected to asecond molding to produce an instant noodle container 9. Meanwhile, theresin composition PHAA-5 described in Comparative Preparation ExampleA-1 and a polystyrene polymer (Styron 685, from Asahi Kasei Corporation)were blended in mass ratios of 75:25 and 51:49 to produce instant noodlecontainers 14 and 15 in the same manner. Further, using only the abovepolystyrene polymer, an instant noodle container 16 was produced in thesame manner. Each mass was 3.0 g per container.

Example B-2

Using resin compositions PHAA-1 to PHAA-4 described in PreparationExamples A-1 to A-4, drink containers 1 to 4 were produced by injectionblow molding. Meanwhile, the resin compositions PHAA-1 to PHAA-4described in Preparation Examples A-1 to A-4 and a lactone polymer(Polycaprolactone, from DAICEL CHEMICAL INDUSTRIES, LTD.) were blendedin a mass ratio of 75:25 to produce drink containers 5 to 8 in the samemanner. They were also blended in a mass ratio of 51:49 in the samemanner to produce drink containers 9 to 12 in the same manner.

Each mass was 3.0 g per container.

Comparative Example B-2

Using a resin composition PHAA-5 described in Comparative PreparationExample A-1, a drink container 9 was produced by injection blow molding.Meanwhile, the resin composition PHAA-5 described in ComparativePreparation Example A-1 and a lactone polymer (Polycaprolactone, fromDAICEL CHEMICAL INDUSTRIES, LTD.) were blended in mass ratios of 75:25and 51:49 to produce drink containers 14 and 15 in the same manner.Further, using only the above lactone polymer, a drink container 16 wasproduced in the same manner.

Each mass was 3.0 g per container.

Example B-3

With respect to an instant noodle container described in Example B-1 orComparative Example B-1, the following evaluation items were tested inorder to compare and evaluate the quality as an instant noodlecontainer. The results are shown in Table 15.

A: good, B: usable, C: unusable, -: untested

Biodegradability: It was checked visually whether or not to be almostinvisible after buried in the soil for 6 months. It should be noted thatB in the table indicates that resin residues were slightly recognizedduring the above period, and C indicates that there was not substantialbiodegradability during the above period.

Quality as instant noodle container: Hardness, brittleness, andfracture/leakage were evaluated at 25° C. (assuming the storage time)and 100° C. (assuming the time to pour hot water).

Tg and Tm: The measurements were performed by a differential scanningcalorimeter (DSC; from PerkinElmer, Inc., Pyris 1, temperatureelevation: 20° C./minute) TABLE 15 25° C. 100° C. Fracture/ Fracture/Container Biodegradability Hardness Brittleness leakage HardnessBrittleness leakage Tg Tm 1 A A A A A A A 91 195 2 A A A A A A A 67 1833 A A A A A A A 55 172 4 A A A A A A A 57 170 5 A A A A A A A — — 6 A AA A A A A — — 7 A A A A A A A — — 8 A A A A A A A — — 9 B A A A A A A —— 10 B A A A A A A — — 11 B A A A A A A — — 12 B A A A A A A — — 13 A C— — C — — 19 158 14 A B A B C — — — — 15 B B A B C — — — — 16 C A A A AA A 93 210

Example B-4

With respect to the drink container described in Example B-2 orComparative Example B-2, the following evaluation items were tested inorder to compare and evaluate the quality as a drink container. Theresults are shown in Table 16.

A: good, B: usable, C: unusable, -: untested

Biodegradability: It was checked visually whether or not to be almostinvisible after buried in the soil for 6 months. It should be noted thatB in the table indicates that resin residues were slightly recognizedduring the above period, and C indicates that there was not substantialbiodegradability during the above period.

Quality as instant noodle container: Hardness, brittleness, andfracture/leakage were evaluated at 25° C. (assuming the storage time)and 100° C. (assuming the time of heat sterilization).

Tg and Tm: The measurement was performed by a differential scanningcalorimeter (DSC; from PerkinElmer, Inc., Pyris 1, temperatureelevation: 20° C./minute). TABLE 16 25° C. 100° C. Fracture/ Fracture/Container Biodegradability Hardness Brittleness leakage HardnessBrittleness leakage Tg Tm 1 A A A A A A A 91 195 2 A A A A A A A 67 1833 A A A A A A A 55 172 4 A A A A A A A 57 170 5 A A A A A A A — — 6 A AA A A A A — — 7 A A A A A A A — — 8 A A A A A A A — — 9 A A A A A A A —— 10 A A A A A A A — — 11 A A A A A A A — — 12 A A A A A A A — — 13 A C— — C — — 19 158 14 A C — — C — — — — 15 A C — — C — — — — 16 A C — — C— — —  60

Besides the above Examples, the molded articles of the present inventionwas experimented under conditions of 40° C. and 140° C., and it wasfound that the molded articles do not have any problem in hardness,brittleness, and fracture/leakage, being excellent in biodegradability.

[Binder Resin]

Next, the polymer blends which are used as binder resins of the presentinvention are shown as follows (Examples C-1 to C-4).

Example C-1

80 g of polylactic acid (Lacty (trade name), from Shimadzu Corporation,melt viscosity at 195° C. 20,000 Pa.s (=200,000 poise), weight averagemolecular weight 200,000) and 120 g of PHA of Preparation Example A-1(PHAA-1) were blended, charged in an injection molding machine, andmelt-kneaded at 195-230° C. for molding. The thus obtained polymer blendwas referred to as PHAC-1 and used as a binder resin.

Example C-2

80 g of polylactic acid (Lacty (trade name), from Shimadzu Corporation,melt viscosity at 195° C. 20,000 Pa.s (=200,000 poise), weight averagemolecular weight 200,000) and 120 g of PHA of Preparation Example A-2(PHAA-2) were blended, charged in an injection molding machine, andmelt-kneaded at 195-230° C. for molding. The thus obtained polymer blendwas referred to as PHAC-2 and used as a binder resin.

(Example C-3

80 g of polylactic acid (Lacty (trade name), from Shimadzu Corporation,melt viscosity at 195° C. 20,000 Pa.s (=200,000 poise), weight averagemolecular weight 200,000) and 120 g of PHA of Preparation Example A-3(PHAA-3) were blended, charged in an injection molding machine, andmelt-kneaded at 195-230° C. for molding. The thus obtained polymer blendwas referred to as PHAC-3 and used as a binder resin.

Example C-4

80 g of polylactic acid (Lacty (trade name), from Shimadzu Corporation,melt viscosity at 195° C. 20,000 Pa.s (=200,000 poise), weight averagemolecular weight 200,000) and 120 g of PHA of Preparation Example A-4(PHAA-4) were blended, charged in an injection molding machine, andmelt-kneaded at 195-230° C. for molding. The thus obtained polymer blendwas referred to as PHAC-4 and used as a binder resin.

Various toners were produced using the polymer blends of the aboveExamples C-1 to C-4 and a single PHA polymer (above Preparation ExamplesA-1 to A-4) and evaluated (Examples D-1 to D-8, Comparative

Examples D-1 and D-2 Example D-1

PHAA-1 (Preparation Example A-1) 100 parts by mass Magenta pigment (C.I.Pigment Red 114)  5 parts by mass Charge controlling agent  2 parts bymass (from Hoechst AG: NXVP 434)

The above composition was mixed and melt-kneaded by a biaxial extruder(L/D=30). The resultant kneaded product was cooled, roughly ground by ahammer mill, finely ground by a jet mill, and then classified to obtainmagenta coloring particles (1) by a grinding method. For the particlesize of the magenta coloring particles (1), the weight average particlesize was 8.1 μm and the ratio of fines was 2.9% by number.

As a fluidity improver, 1.5 parts by mass of hydrophobic silica finepowder (BET: 250 m²/g) treated with hexamethyldisilazane were dry-mixedwith 100 parts by mass of the magenta coloring particles (1) by aHenshel mixer, whereby a magenta toner (1) of this Example was obtained.In addition, 7 parts by mass of the resultant magenta toner (1) weremixed with 93 parts by mass of a resin-coated magnetic ferrite carrier(average particle size: 45 μm) to prepare a two-component type magentadeveloper (1) for magnetic brush development.

Examples D-2 to D-8

Magenta toners (2) to (8) of Examples D-2 to D-8 were obtained in thesame manner as in Example D-1 except that 100 parts by mass of each ofPHAA-2 to PHAA-4 and PHAC-1 to PHAC-4 were used in place of PHAA-1. Theproperties of the toners were measured in the same manner as in ExampleD-1, and the results are shown in Table 17. In addition, two-componenttype magenta developers (2) to (8) were obtained in the same manner asin Example D-1 using the toners, respectively.

Comparative Example D-1

A magenta toner (9) of Comparative Example D-1 was obtained in the samemanner as in Example D-1 except that 100 parts by mass of astyrene-butylacrylate copolymer resin (glass transition temperature 70°C.) was used in place of PHAA-1. The properties of the toner weremeasured in the same manner as in Example D-1, and the results are shownin Table 17. In addition, a two-component type magenta developer (9) ofComparative Example D-1 was obtained in the same manner as in ExampleD-1 using the toner.

<Evaluation>

For the two-component type magenta developers (1) to (8) obtained in theabove Examples D-1 to D-8 and the two-component type magenta developer(9) obtained in Comparative Example D-1, the charge levels of the tonersafter stirring for 10 and 300 seconds were measured under conditions ofnormal temperature and normal humidity (25° C., 60% RH) and hightemperature and high humidity (30° C., 80% RH) using the previouslydescribed method for measuring charge levels. Then, numbers frommeasurement values of two-component blow-off charge levels were roundedoff to one decimal place to make evaluations according to the followingcriteria. The results are shown together in Table 17. TABLE 17Electrification property of magenta toners (1) to (9) ElectrifiabilityNormal High Particle size temperature temperature distribution andnormal and high Weight Ratio of humidity (Q/M) humidity (Q/M) Toneraverage fines Stirring Stirring Stirring Stirring Number Number:particle (% by for 10 for 300 for 10 for 300 Examples of PHA Red size(μm) number) seconds seconds seconds seconds D-1 PHAA-1 1 8.1 2.9 A E AE D-2 PHAA-2 2 7.9 2.7 A E A E D-3 PHAA-3 3 8.1 3.0 E E E E D-4 PHAA-4 48.2 3.3 E E E E D-5 PHAC-1 5 8.4 4.0 A E A E D-6 PHAC-2 6 8.3 3.5 A E AE D-7 PHAC-3 7 8.4 4.3 E E E E D-8 PHAC-4 8 8.7 3.9 E E E E Comparative— 9 7.0 4.9 E E E E Example D-1<Electrifiability>E: Excellent (−20 μC/g or lower)A: Good (−19.9 to −10.0 μC/g)B: Usable (−9.9 to −5.0 μC/g)C: Unusable (−4.9 μC/g or higher)

Examples D-9 to D-16

Black toners (1) to (8) of Examples D-9 to D-16 were obtainedrespectively in the same manner as in Example D-1 except that 100 partsby mass of PHAA-1 to PHAA-4 and PHAC-1 to PHAC-4 were used, and a carbonblack (DBP oil absorption 110 ml/100 g) was used in place of the magentapigment. The properties of the toners were measured in the same manneras in Example D-1, and the results are shown in Table 18. In addition,two-component type black developers (1) to (8) were obtained in the samemanner as in Example D-1 using the toners.

Comparative Example D-2

A black toner (9) of Comparative Example D-2 was obtained in the samemanner as in Example D-1 except that 100 parts by mass of astyrene-butylacrylate copolymer resin (glass transition temperature 70°C.) was used in place of PHAA-1 and a carbon black (DBP oil absorption110 ml/100 g) was used in place of the magenta pigment. The propertiesof the toner were measured in the same manner as in Example D-1, and theresults are shown in Table 18. In addition, a two-component type blackdeveloper (9) of Comparative Example D-2 was obtained in the same manneras in Example D-1 using the toner.

<Evaluation>

For the two-component type black developer (1) to (8) obtained in theabove Examples D-9 to D-16 and the two-component type black developer(9) obtained in Comparative Example D-2, the charge levels of the tonersafter stirring for 10 and 300 seconds were measured under conditions ofnormal temperature and normal humidity (25° C., 60% RH) and hightemperature and high humidity (30° C., 80% RH) using the previouslydescribed method for measuring charge levels. Then, numbers frommeasurement values of two-component blow-off charge levels were roundedoff to one first decimal place to make evaluations according to thefollowing criteria. The results are shown together in Table 18. TABLE 18Electrification property of black toners (1) to (9) ElectrifiabilityNormal High Particle size temperature temperature distribution andnormal and high Weight Ratio of humidity (Q/M) humidity (Q/M) Toneraverage fines Stirring Stirring Stirring Stirring Number Number:particle (% by for 10 for 300 for 10 for 300 Examples of PHA Black size(μm) number) seconds seconds seconds seconds D-9  PHAA-1 1 7.3 3.2 A E AE D-10 PHAA-2 2 7.7 2.9 A E A E D-11 PHAA-3 3 7.3 3.1 E E E E D-12PHAA-4 4 8.0 3.5 E E E E D-13 PHAC-1 5 8.1 3.3 A E A E D-14 PHAC-2 6 7.93.9 A E A E D-15 PHAC-3 7 8.2 4.1 E E E E D-16 PHAC-4 8 8.3 3.7 E E E EComparative — 9 7.5 4.2 E E E E Example D-2<Electrifiability>E: Excellent (−20 μC/g or lower)A: Good (−19.9 to −10.0 μC/g)B: Usable (−9.9 to −5.0 μC/g)C: Unusable (−4.9 μC/g or higher)

Example D-17

<Deinking Property Test>

Test paper was produced by forming test images with a black and whiteratio of 6% on the paper surface of 75 g/m² by using the black toners(1) to (9) obtained in Examples D-9 to D-16 and Comparative Example D-2.A hand-made sheet for evaluation was produced with following conditionsby using the test paper. Disaggregation: An aqueous dispersion of thefollowing composition was stirred in a beaker at 50° C. for 20 minutesto be disaggregated. Test paper 5.0% NaOH 0.7% Sodium silicate 3.0% H₂O₂1.0%

Deinking agent (from Lion Corporation, “Liptol S 2800”) 0.2%Dilution/dehydration/kneader treatment: Water was added to the aboveaqueous dispersion to dilute to 5%. The mixture was dehydratedcentrifugally, and pulp, sodium silicate and the like were added to makethe proportion of 20% of pulp, 3.0% of sodium silicate, and 0.5% of NaOHand disaggregated by a kneader. Aging: The kneader-disaggregated productwas aged at 50° C. for 2 hours. Flotation: Water was added to the agedproduct to prepare a dispersion with pulp concentration of 1%, and finebubbles were discharged into the dispersion for 7 minutes. The toner inthe solution was adsorbed to the bubbles and floated on the watersurface to separate the toner and water. Washing: 2.4 g of pulpsubjected to deinking was washed with two portions of 1 liter of water.Preparation of hand-made sheet for test: A hand-made sheet (basis weight100 g/m²) was produced by a tappet sheet machine. Evaluation of deinkingproperty: The number of the toners existing in 9 cm² of the hand-madesheet was evaluated visually and microscopically by classifying thetoners into two sizes of 100 μm or larger (visible visually) and 60 to100 μm.

The results of the above test are shown in Table 19. The values in thetable indicate the number of the remaining toners. TABLE 19 Results ofdeinking property test 60 to 100 μm 100 μm or larger Total Number NumberNumber Example D-9 12 10 22 Example D10 11 9 20 Example D11 8 9 17Example D12 7 9 16 Example D13 13 15 28 Example D14 10 13 23 Example D1511 14 25 Example D16 9 11 20 Comparative 43 38 81 Example D-2

Example D-18

<Biodegradability Test>

Red toners (1) to (8), black toners (1) to (8), comparative red toner(9), and comparative black toner (9) were melt-molded to films withthickness of about 50 μm and buried in the soil for 6 months. As aresult, films of red toners (1) to (8) and black toners (1) to (8) lostthe shapes completely. On the other hand, the shapes of comparative redtoner (9) and comparative black toner (9) remain intact.

Examples D-19 to D-34 and Comparative Examples D-3 and D-4

First, an image forming apparatus used in the image forming methods ofExamples D-19 to D-34 and Comparative Examples D-3 and D-4 will bedescribed. FIG. 1 is a schematic explanatory view of the cross sectionof an image forming apparatus for carrying out the image forming methodsof Examples and Comparative Examples of the present invention. Aphotoconductor drum 1 shown in FIG. 1 has a photosensitive layer 1 ahaving an organic photo semiconductor on a substrate 1 b, and isconFig.d to rotate in the direction indicated by the arrow, and itssurface is electrically charged at a potential of about −600 V by acharge roller 2 being a charge member situated opposite to thephotoconductor drum 1 and contacting and rotating with the drum. Asshown in FIG. 1, the charge roller 2 has a cored bar 2 b covered with aconductive elastic layer 2 a.

Next, the photoconductor drum 1 with its surface electrically charged isexposed to light 3 and at this time, on/off operations are performed onthe photoconductor by a polygon mirror according to digital imageinformation, whereby an electrostatic latent image with the potential ofthe exposed area being −100 V and the potential of the dark area being−600 V is formed. Subsequently, this electrostatic latent image on thephotoconductor drum 1 is reverse-developed and thereby actualized usinga plurality of development apparatuses 4-1, 4-2, 4-3 and 4-4, and thus atoner image is formed on the photoconductor drum 1. At this time, thetwo-component type developers obtained in Examples D-1 to D-16 andComparative Examples D-1 and D-2 were respectively used as developers toform a toner image with a magenta toner or a black toner. FIG. 2 is anenlarged sectional view of principal parts of development apparatuses 4for two-component type developers used at that time. Then, the tonerimage on the photoconductor drum 1 is transferred to an intermediatetransfer body 5 contacting and rotating with the photoconductor drum 1.As a result, a four-color color combination developed image is formed onthe intermediate transfer body 5. A non-transferred toner remaining onthe photoconductor drum 1 without being transferred is collected in acontainer 9 for residual toners by a cleaner member 8.

The intermediate transfer body 5 is constituted by a cored bar 5 b as asupport and an elastic layer 5 a provided thereon as shown in FIG. 1. Inthis Example, the intermediate transfer body 5 having the cored bar 5 bcoated with the elastic layer 5 a with a carbon black as a conductivityproducer sufficiently dispersed in nitrile-butadiene rubber (NBR) wasused. The degree of hardness of the elastic layer 5 a measured inaccordance with “JIS K-6301” was 30 degrees, and the volume resistivitywas 10⁹ Ω.cm. The level of transfer current required for transferringthe image from the photoconductor drum 1 to the intermediate transferbody 5 is about 5 μA, and this level of current was obtained by adding avoltage of +500 V to the cored bar 5 b.

The four-color toner color combination visible image formed on theintermediate transfer body 5 is transferred to an object transferringmaterial such as a paper by a transfer roller 7, and is thereafter fixedby a heat-fixation apparatus H. The transfer roller 7 is providedthereon the core metal 7 b with the outside diameter of 10 mm on whichan elastic layer 7 a is formed by coating of a foam ofethylene-propylene-diene based tridimensional copolymer (EPDM)dispersing carbon sufficiently therein as a conductivity producingmaterial. The layer had a volume specific resistance of 10⁶Ω.cm and ahardness degree of 35° as measured in accordance with “JIS K-6301”. Inaddition, a voltage was applied to this transfer roller 7 to pass atransfer current of 15 μA therethrough.

In the apparatus shown in FIG. 1, a fixation apparatus of heated rolltype having no oil coating mechanism shown in FIGS. 5 and 6 was used inthe heat-fixation apparatus H. The both upper and lower rollers of thefixation apparatus used here had surface layers made of fluorine basedresin. In addition, the diameter of the roller was 60 mm. The fixationtemperature for fixation was 160° C., and the nipping width was set at 7mm. Furthermore, a transfer residual toner on the photoconductor drum 1,which was collected by cleaning, was transported to a developing deviceby a reuse mechanism for reuse.

<Evaluation>

Two-component type developers produced using the toners of Examples D-1to D-16 and two-component type developers produced using toners ofComparative Examples D-1 and D-2 were used, respectively, to performprintout testing at a printout rate of 8 sheets (A4 size) per minutewhile the developer was supplied one after another in a monochromaticintermittent mode (namely a mode in which the developing device isstopped for 10 seconds for each printout to accelerate the degradationof a toner in a preliminary operation during restart of the device) at anormal temperature and normal humidity (25° C., 60% RH) and a hightemperature and high humidity (30° C., 80% RH) under the conditionsdescribed above, and resulting printout images were evaluated for thefollowing items. The evaluation results are shown together in Table 20.

(Evaluation of printout images)

1. Image Density

Images were printed out on a predetermined number of normal copyingpapers (75 g/m²), and the image density was evaluated according to thelevel at which the density of the image from the final printout wasretained with respect to the density of the initial image. Furthermore,for the measurement of image density, a Macbeth reflective densitometer(manufactured by Macbeth Co., Ltd.) was used to measure a densityrelative to that of the printout image on a white ground with thedensity of original copy equal to 0.00. E: Excellent (image density fromthe final printout is 1.40 or greater) A: Good (image density from thefinal printout is 1.35 or greater and lower than 1.40) B: Usable (imagedensity from the final printout is 1.00 or greater and lower than 1.35)C: Unusable (image density from the final printout is lower than 1.00)2. Image fog

Images were printed out on a predetermined number of normal copyingpapers (75 g/m²), and the image fog was evaluated with a solid whiteimage from the final printout. Specifically, the evaluation was made asfollow: the worst value of the reflective density of the white groundafter printing and the average reflective density of the paper beforeprinting, as measured using a reflective densitometer (ReflectometerODEL TC-6DS manufactured by Tokyo Denshoku Co., Ltd.), were defined asDS and Dr, respectively, (Ds-Dr) was calculated from these values as afog level to make an evaluation according to the following criterion. E:Excellent (fog level is 0% or higher and lower than 1.5%) A: Good (foglevel is 1.5% or higher and lower than 3.0%) B: Usable (fog level is3.0% or higher and lower than 5.0%) C: Unusable (fog level is 5.0% orhigher)

3. Transferability

Solid black images were printed out on a predetermined number of normalcopying papers (75 g/m²), and the image dislocation level of the imagefrom the final printout was visually observed to make an evaluationaccording to the following criterion. E: Excellent (almost not observed)A: Good (slightly observed) B: Usable C: Unusable

In addition, in Examples D-19 to D-34 and Comparative Examples D-3 andD-4, occurrences of scars and sticking residual toners on the surfacesof the photoconductor drum and intermediate transfer body, and theirinfluence on printout images (matching with the image forming apparatus)were visually evaluated after 5000 images were outputted, and as theresult, scars and sticking residual toners on the surfaces of thephotoconductor drum and intermediate transfer body were not observed,and thus matching with the image forming apparatus was excellent. TABLE20 Evaluation result of printout image Normal temperature and Hightemperature Examples/ normal humidity and high humidity ComparativeTwo-component Image Transfer- Image Transfer- Examples type developerdensity Image fog ability density Image fog ability D-19 Red 1 E A E E AE D-20 Red 2 E A E E A A D-21 Red 3 E E E E E E D-22 Red 4 E E E E E ED-23 Red 5 E A E E A E D-24 Red 6 E A E E A A D-25 Red 7 E E E E E ED-26 Red 8 E E E E E E D-27 Black 1 E A E E A E D-28 Black 2 E A E E A AD-29 Black 3 E E E E E E D-30 Black 4 E E E E E E D-31 Black 5 E A E E AE D-32 Black 6 E A E E A A D-33 Black 7 E E E E E E D-34 Black 8 E E E EE E Comparative Red 9 E E E E E E Example D-3 Comparative Black 9 E E EE E E Example D-4

Example D-35 to Example D-42, Comparative Example D-5 and ComparativeExample D-6

For carrying out the image forming methods of Example D-35 to ExampleD-42 and Comparative Example D-5 and Comparative Example D-6, the tonersobtained in Examples D-9 to D-16 and Comparative Examples D-1 and D-2were used respectively as developers. In addition, for means for formingan image, an image forming apparatus with a commercially available laserbeam printer LBP-EX (from Canon Inc.) modified so that it was providedwith a reuse mechanism and reset as shown in FIG. 3 was used. That is,the image forming apparatus shown in FIG. 3 is provided with a system inwhich a non-transferred toner remaining on the photoconductor drum 20after the transfer process is scraped off by an elastic blade 22 of acleaner 21 abutting against the photoconductor drum 20, then sent intothe cleaner 21 by a cleaner roller, passed through a cleaner reuse 23,and returned to the development device 26 via a hopper 25 by a supplypipe 24 with a carrier screw mounted thereon, and the toner collected inthis way is reused.

In the image forming apparatus shown in FIG. 3, the surface of thephotoconductor drum 20 is electrically charged by a primary chargeroller 27. A rubber roller (diameter 12 mm, abutment pressure 50 g/cm)coated with a nylon resin and having conductive carbon dispersed thereinwas used for the primary charge roller 27, and an electrostatic latentimage with a dark area potential VD of −700 V and a light area potentialVL of −200 V was formed on the electrostatic latent image carrier(photoconductor drum 20) by laser exposure (600 dpi, not shown). As atoner carrier, a development sleeve 28 having a surface roughness Ra of1.1 with the surface coated with a resin having a carbon black dispersedthereon was used.

An enlarged sectional view of the principal part of the developmentapparatus for one-component type developers used in Example D-35 toExample D-52 and Comparative Example D-5 and Comparative Example D-6 isshown in FIG. 4. For conditions for developing electrostatic latentimages, the speed of the development sleeve 28 was set at a speed 1.1times as high as the movement speed of the surface of the photoconductordrum 20 opposite thereto, and the space α between the photoconductordrum 20 and the development sleeve 28 (between S and D) was 270 μm. Forthe member for controlling the thickness of the toner layer, an abuttingurethane rubber blade 29 was used. In addition, the set temperature ofthe heat-fixation apparatus for fixing a toner image was 160° C.Furthermore, for the fixation apparatus, a fixation apparatus shown inFIG. 5 and FIG. 6 was used. In FIG. 32, the part referred to with areference numeral 32 is tension free.

As described above, under the condition of normal temperature and normalhumidity (25° C., 60% RH), images were printed out on up to 30,000sheets at a printout rate of 8 sheets (A4 size) per minute while thetoner was supplied one after another in a continuous mode (namely, amode in which the development device is not stopped, thereby promotingconsumption of the toner), and the densities of resulting printoutimages were measured to evaluate the durability of the image accordingto the following criteria. In addition, the image from the 10,000thprintout was observed to make an evaluation about image fog according tothe following criteria. At the same time, situations of the componentscomprising the image forming apparatus after the durability testing wereobserved to evaluate matching between each component and the abovetoners. The results thereof are shown together in Table 21. Change inimage density during endurance

Images were printed out on a predetermined number of normal copyingpapers (75 g/m²), and the image density was evaluated according to thelevel at which the density of the image from the final printout wasretained with respect to the density of the initial image. Furthermore,for the measurement of image density, a Macbeth reflective densitometer(from Macbeth Co., Ltd.) was used to measure a density relative to thatof the printout image on a white ground with the density of originalcopy equal to 0.00 for evaluation. E: Excellent (image density from thefinal printout is 1.40 or greater) A: Good (image density from the finalprintout is 1.35 or greater and lower than 1.40) B: Usable (imagedensity from the final printout is 1.00 or greater and lower than 1.35)C: Unusable (image density from the final printout is lower than 1.00)

Image Fog

Images were printed out on a predetermined number of normal copyingpapers (75 g/m²), and the image fog was evaluated with a solid whiteimage from the final printout. Specifically, the evaluation was made asfollows: the worst value of the reflective density of the white groundafter printing and the average reflective density of the paper beforeprinting, as measured using a reflective densitometer (ReflectometerODEL TC-6DS from Tokyo Denshoku Co., Ltd.), were defined as Ds and Dr,respectively, and (Ds-Dr) was calculated from these values as a foglevel to make an evaluation according to the following criteria. E:Excellent (fog level is 0% or higher and lower than 1.5%) A: Good (foglevel is 1.5% or higher and lower than 3.0%) B: Usable (fog level is3.0% or higher and lower than 5.0%) C: Unusable (fog level is 5.0% orhigher) Evaluation of matching with image forming apparatus

1. Matching with Development Sleeve

After the printout testing was completed, the situation of residualtoners sticking to the surface of the development sleeve and theirinfluence on the printout image were visually evaluated. E: Excellent(not observed) A: Good (almost not observed) B: Usable (stickingresidual toners are observed but the influence on the image is notsignificant) C: Unusable (sticking of residual toners is significant,causing unevenness in the image)

2. Matching with Photoconductor Drum

Occurrences of scars and sticking residual toners on the surface of thephotoconductor drum and their influence on the printout image werevisually evaluated. E: Excellent (not observed) A: Good (scars areslightly observed but no influence on the image) B: Usable (stickingresidual toners and scars are observed but the influence on the image isnot significant) C: Unusable (sticking of residual toners issignificant, causing longitudinal striped defects in the image)

3. Matching with Fixation Apparatus

The surface situation of the fixation film was observed, and the resultsof surface characteristics and occurrences of sticking residual tonerswere collectively averaged to evaluate the durability of the film.

(1) Surface Characteristics

Occurrences of scars and flaking on the surface of the fixation filmwere visually observed and evaluated after the printout testing wascompleted. E: Excellent (not observed) A: Good (almost not observed) B:Usable C: Unusable

(2) Situation of Sticking Residual Toners

The situation of residual toners sticking to the surface of the fixationfilm was visually observed and evaluated after the printout testing wascompleted. E: Excellent (not observed) A: Good (almost not observed) B:Usable C: Unusable TABLE 21 Evaluation results of printout image andmatching with image forming apparatus Evaluation of printout imageEvaluation of matching with each Change in image density duringapparatus endurance 10 thousands Photo- Fixation apparatus 10 30 foggedDevelopment conductor Surface Toner Examples Toner Initial Thousandthousands thousands images sleeve drum characteristic fixation D-35Black 1 E E E A E E E E A D-36 Black 2 E E A A E E E E A D-37 Black 3 EE E E E E E E E D-38 Black 4 E E E E E E E E E D-39 Black 5 E E E A E EE E A D-40 Black 6 E E A A A E A E A D-41 Black 7 E E E E E E E E E D-42Black 8 E E E E E E E E E Comparative Red 9 E E E E E E E E E ExampleD-5 Comparative Black 9 E E E E E E E E E Example D-6

Example D-43

Printout testing was performed in the same manner as in Example D-42except that the toner reuse mechanism of the image forming apparatus ofFIG. 3 was removed and a printout rate was set to 16 sheets (A4 size)per minute, while the black toner (1) of Example D-1 was supplied oneafter another in a continuous mode (namely, a mode in which thedevelopment device is not stopped, thereby promoting consumption of thetoner). The resultant printout images and the matching with the imageforming apparatus used were evaluated in the same items as those ofExample D-35 to Example D-42 and Comparative Example D-5 and ComparativeExample D-6. As a result, good results were obtained for all the items.

1. A polyhydroxyalkanoate copolymer comprising at least, per polymermolecule, one kind of unit selected from the group consisting ofchemical formulae (1) and (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COO R′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and at least one unit selected from the group consisting ofchemical formulae (3) to (6):

(wherein m is an integer selected from the range shown in the samechemical formula; Rz comprises a residue having either a phenylstructure or a thienyl structure; and when more than one unit exist, mand Rz of each unit can independently represent any one of the integersand the substituents described above, respectively)

(wherein R_(a) is any one selected from the group consisting of H, CN,NO₂, halogen, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇; k is an integerselected from the range shown in the same chemical formula; and whenmore than one unit exist, k and R_(a) of each unit can independentlyrepresent any one of the integers and the substituents described above,respectively)

(wherein n is an integer selected from the range shown in the samechemical formula, and when more than one unit exist, n of each unit canrepresent any one of the integers described above independently)

(wherein n is an integer selected from the range shown in the samechemical formula; R_(b) is any one selected from the group consisting ofH, Na and K; and when more than one unit exist, n and R_(b) of each unitcan independently represent any one of the integers and the substituentsdescribed above, respectively).
 2. The polyhydroxyalkanoate copolymeraccording to claim 1, further comprising, per polymer molecule, at leastone unit selected from the group consisting of 3-hydroxy-(substitutedphenylsulfanyl)alkanoic acid units having chemical formula (7):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COO R′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit).
 3. The polyhydroxyalkanoate copolymer according to claim 1,wherein Rz in chemical formula (3) is any one residue selected from thegroup consisting of chemical formulae (8), (9), (10), (11), (12), (13),(14) and (15):

(wherein R₁ is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′ except the substituent introduced into the para-positionof the phenyl group (R′ is any one selected from the group consisting ofH, Na and K), CH₃, C₂H₅, C₃H₇, CH═CH₂, CF₃, C₂F₅ and C₃F₇, and when morethan one unit exist, R₁ of each unit can represent any one of thesubstituents described above independently)

(wherein R₂ is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, SCH₃, CF₃, C₂F₅ and C₃F₇, and when more thanone unit exist, R₁ of each unit can represent any one of thesubstituents described above independently)

(wherein R₃ is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇, and when more than oneunit exist, R₃ of each unit can represent any one of the substituentsdescribed above independently)

(wherein R₅ is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R₅ of eachunit can represent any one of the substituents described aboveindependently)

and when more than one unit exist, Rz of each unit can represent any oneof the residues described above independently.
 4. Thepolyhydroxyalkanoate copolymer according to claim 1, which has a numberaverage molecular weight of 1,000 to 1,000,000.
 5. A process ofpreparing a polyhydroxyalkanoate copolymer comprising, per polymermolecule, a 3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unithaving chemical formula (7):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and at least one unit selected from the group consisting ofunits having chemical formulae (20), (4) and (5):

(wherein m is an integer selected from the range shown in the samechemical formula; Rx comprises a residue having either a phenylstructure or a thienyl structure; and when more than one unit exists, mand Rx of each unit can independently represent any one of the integersand the substituents described above, respectively)

(wherein R_(a) is any one selected from the group consisting of H, CN,NO₂, halogen, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇; k is an integerselected from the range shown in the same chemical formula; and whenmore than one unit exist, k and R_(a) of each unit can independentlyrepresent any one of the integers and the substituents described above,respectively)

(wherein n is an integer selected from the range shown in the samechemical formula, and when more than one unit exist, n of each unit canrepresent any one of the integers described above independently), whichcomprises the steps of: allowing a microorganism capable of producingthe polyhydroxyalkanoate copolymer to biosynthesize thepolyhydroxyalkanoate copolymer under the condition that at least oneω-(substituted phenylsulfanyl)alkanoic acid having chemical formula(16):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and s is an integer selected from 1 to 7 and can differfor each unit) and at least one compound selected from the groupconsisting of compounds having chemical formulae (17), (18) and (19):

(wherein q is an integer selected from the range shown in the samechemical formula; and Rx comprises a residue having either a phenylstructure or a thienyl structure)

(wherein R_(a) is any one selected from the group consisting of H, CN,NO₂, halogen, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇; r is an integerselected from the range shown in the same chemical formula)

(wherein p is an integer selected from the range shown in the samechemical formula) exist.
 6. The process of preparing apolyhydroxyalkanoate copolymer according to claim 5, wherein thecondition is comprised of cultivating the microorganism in a medium thatcomprises at least one ω-(substituted phenylsulfanyl)alkanoic acidhaving chemical formula (16) and at least one compound selected from thegroup consisting of compounds having chemical formulae (17) to (19). 7.The process of preparing a polyhydroxyalkanoate copolymer according toclaim 6, wherein the medium further comprises at least one selected fromthe group consisting of peptides, yeast extract, organic acids or thesalts thereof, amino acids or salts thereof, saccharides, andstrait-chain alkanoic acids with 4 to 12 carbon atoms or the saltsthereof.
 8. The process of preparing a polyhydroxyalkanoate copolymeraccording to claim 7, wherein the petides are polypeptone; the organicacids or the salts thereof are pyruvic acid, oxalacetic acid, citricacid, isocitric acid, ketoglutaric acid, succinic acid, fumaric acid,malic acid, lactic acid and the salts thereof; the amino acids or thesalts thereof are glutamic acid, aspartic acid and the salts thereof;and the saccharides are glyceraldehyde, erythrose, arabinose, xylose,glucose, galactose, mannose, fructose, glycerol, erythritol, xylitol,gluconic acid, glucuronic acid, galacturonic acid, maltose, sucrose andlactose.
 9. The process of preparing a polyhydroxyalkanoate copolymeraccording to claim 6, comprising a step of recovering thepolyhydroxyalkanoate copolymer produced by the microorganism from thecells of the microorganism.
 10. The process of preparing apolyhydroxyalkanoate copolymer according to claim 5, wherein themicroorganism is one classified as Pseudomonas sp.
 11. The process ofpreparing a polyhydroxyalkanoate copolymer according to claim 10,wherein the microorganism is any one or more strains selected from thegroup consisting of Pseudomonas cichorii YN2 (FERM BP-7375), Pseudomonascichorii H45 (FERM BP-7374) and Pseudomonas jessenii P161 (FERMBP-7376).
 12. A process of preparing a polyhydroxyalkanoate copolymercomprising, per polymer molecule, at least one unit selected from thegroup consisting of formulae (1) and (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and at least one unit selected from the group consisting ofchemical formulae (3) to (6):

(wherein m is an integer selected from the range shown in the samechemical formula; Rz comprises a residue having either a phenylstructure or a thienyl structure; and when more than one unit exist, mand Rz of each unit can independently represent any one of the integersand the substituents described above, respectively)

(wherein R_(a) is any one selected from the group consisting of H, CN,NO₂, halogen, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇; k is an integerselected from the range shown in the same chemical formula; and whenmore than one unit exist, k and R_(a) of each unit can independentlyrepresent any one of the integers and the substituents described above,respectively)

(wherein n is an integer selected from the range shown in the samechemical formula, and when more than one unit exist, n of each unit canrepresent any one of the integers described above independently)

(wherein n is an integer selected from the range shown in the samechemical formula; R_(b) is any one selected from the group consisting ofH, Na and K; and when more than one unit exist, n and R_(b) of each unitcan independently represent any one of the integers and the substituentsdescribed above, respectively), which comprises the steps of: employingas a raw material a polyhydroxyalkanoate copolymer comprising, perpolymer molecule, a 3-hydroxy-(substituted phenylsulfanyl)alkanoic acidunit having chemical formula (7):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and at least one unit selected from the group consisting ofchemical formulae (4), (5) and (20):

(wherein m is an integer selected from the range shown in the samechemical formula; Rx comprises a residue having either a phenylstructure or a thienyl structure; and when more than one unit exists, mand Rx of each unit can independently represent any one of the integersand the substituents described above, respectively) and oxidizing at atime the 3-hydroxy-(substituted phenylsulfanyl)alkanoic acid unit havingchemical formula (7) and the at least one unit selected from the groupconsisting of chemical formulae (4), (5) and (20).
 13. The process ofpreparing a polyhydroxyalkanoate copolymer according to claim 12,wherein the polyhydroxyalkanoate copolymer as the raw material isprepared by any one process selected from the group consisting ofprocesses according to claims 5 to
 11. 14. The process of preparing apolyhydroxyalkanoate copolymer according to claim 13, wherein theoxidation is conducted using one or more oxidizing agents selected fromthe group consisting of permanganate, bichromate, periodate, hydrogenperoxide, sodium percarbonate, metachloroperbenzoate, performic acid andperacetic acid.
 15. The process of preparing a polyhydroxyalkanoatecopolymer according to claim 14, wherein the oxidizing agent ispermanganate and the oxidizing treatment is performed under acidicconditions.
 16. The process of preparing a polyhydroxyalkanoatecopolymer according to claim 13, wherein the oxidization is conductedusing ozone.
 17. The process of preparing a polyhydroxyalkanoatecopolymer according to claim 12, wherein Rz in chemical formula (3) isat least any one kind of residue selected from the group consisting ofchemical formulae (8), (9), (10), (11), (12), (13), (14) and (15):

(wherein R₁ is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′ except the substituent introduced into the para-positionof the phenyl group (R′ is any one selected from the group consisting ofH, Na and K), CH₃, C₂H₅, C₃H₇, CH═CH₂, CF₃, C₂F₅ and C₃F₇, and when morethan one unit exist, R₁ of each unit can represent any one of thesubstituents described above independently)

(wherein R₂ is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, SCH₃, CF₃, C₂F₅ and C₃F₇, and when more thanone unit exist, R₁ of each unit can represent any one of thesubstituents described above independently)

(wherein R₃ is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, CF₃, C₂F₅ and C₃F₇, and when more than oneunit exist, R₃ of each unit can represent any one of the substituentsdescribed above independently)

(wherein R₅ is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R₅ of eachunit can represent any one of the substituents described aboveindependently)

and Rx in chemical formula (20) is at least any one kind of residueselected from the group consisting of chemical formulae (9), (10), (11),(12), (13), (14), (15) and (21):

(wherein Rc is any one selected from the group consisting of H, halogen,CN, NO₂, CH₃, C₂H₅, C₃H₇, CH═CH₂, CF₃, C₂F₅ and C₃F₇ , and when morethan one unit exist, Rc of each unit can represent any one of thesubstituents described above independently).
 18. A resin compositioncomprising a resin (A) that is comprised of a polyhydroxyalkanoatecomprising, per polymer molecule, at least one unit selected from thegroup consisting of 3-hydroxy-(substituted phenylsulfinyl)alkanoic acidunits having chemical formula (1) and 3-hydroxy-(substitutedphenylsulfonyl)alkanoic acid units having chemical formula (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and a thermoplastic resin (B) that comprises no unit selectedfrom the group consisting of 3-hydroxy-(substitutedphenylsulfinyl)alkanoic acid units having chemical formula (1) and3-hydroxy-(substituted phenylsulfonyl)alkanoic acid units havingchemical formula (2), the content of the resin (A) being higher thanthat of the resin (B) in terms of mass percentage.
 19. The resincomposition according to claim 18, wherein the thermoplastic resin (B)is comprised of one or more resins selected from the group consisting ofpolyester-based resin, polystyrene-based resin, polypropylene-basedresin, polyethylene terephthalate-based resin, polyurethane-based resin,polyvinyl-based resin and polyamide-based resin.
 20. The resincomposition according to claim 19, wherein the polystyrene-based resinis polystyrene.
 21. The resin composition according to claim 19, whereinthe polyester-based resin is poly-κ-caprolactone or polylactic acid. 22.The resin composition according to claim 18, further comprising anadditive for resin.
 23. A resin composition comprising a resin (A) thatis comprised of a polyhydroxyalkanoate comprising, per polymer molecule,at least one unit selected from the group consisting of3-hydroxy-(substituted phenylsulfinyl)alkanoic acid units havingchemical formula (1) and 3-hydroxy-(substituted phenylsulfonyl)alkanoicacid units having chemical formula (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit) and an additive for resin.
 24. A resin for being decomposed bymicroorganisms comprising: the resin comprising a polyhydroxyalkanoatecomprising, per polymer molecule, at least one unit selected from thegroup consisting of 3-hydroxy-(substituted phenylsulfinyl)alkanoic acidunits having chemical formula (1) and 3-hydroxy-(substitutedphenylsulfonyl)alkanoic acid units having chemical formula (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit).
 25. A method of decomposing a resin comprising the steps of:providing the resin; decomposing the resin in contacting withmicroorganisms, wherein the resin comprises a polyhydroxyalkanoatecomprising, per polymer molecule, at least one unit selected from thegroup consisting of 3-hydroxy-(substituted phenylsulfinyl)alkanoic acidunits having chemical formula (1) and 3-hydroxy-(substitutedphenylsulfonyl)alkanoic acid units having chemical formula (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit).
 26. A binder resin for forming a resin-based powder orgranular material, wherein the binder resin comprises apolyhydroxyalkanoate comprising, per polymer molecule, at least one unitselected from the group consisting of 3-hydroxy-(substitutedphenylsulfinyl)alkanoic acid units having chemical formula (1) and3-hydroxy-(substituted phenylsulfonyl)alkanoic acid units havingchemical formula (2):

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor each unit)

(wherein R is any one selected from the group consisting of H, halogen,CN, NO₂, COOR′, SO₂R″ (R′ is any one selected from the group consistingof H, Na, K, CH₃ and C₂H₅; R″ is any one selected from the groupconsisting of OH, ONa, OK, halogen, OCH₃ and OC₂H₅), CH₃, C₂H₅, C₃H₇,(CH₃)₂—CH and (CH₃)₃—C, and when more than one unit exist, R of eachunit can represent any one of the substituents described aboveindependently; and x is an integer selected from 1 to 7 and can differfor unit).
 27. The binder resin according to claim 26, furthercomprising a thermoplastic resin other than the polyhydroxyalkanoate,wherein the content of the polyhydroxyalkanoate is higher than that ofthe thermoplastic resin in content by weight.
 28. The binder resinaccording to claim 27, wherein the thermoplastic resin is one or moreselected from the group consisting of polycaprolactone and polylacticacid.
 29. The binder resin according to claims 26, wherein the numberaverage molecular weight of the binder resin is 2,000 or more and300,000 or less.
 30. The binder resin according to claims 26, whereinthe glass transition point of the binder resin is 30 to 80° C. and thesoftening point of the same is 60 to 170° C.
 31. The binder resinaccording to claim 26, wherein the resin-based powder or granularmaterial is a toner for developing electrostatic charge images.
 32. Atoner for developing electrostatic charge images, wherein the tonercomprises the binder resin according to claims
 26. 33. A method forforming an image comprising the steps of: charging an electrostaticlatent image carrier by applying voltage to a charging member fromoutside; forming an electrostatic charge image on the chargedelectrostatic latent image carrier; developing the electrostatic chargeimage with a toner for developing electrostatic charge images to form atoner image on the electrostatic latent image carrier; transferring thetoner image on the electrostatic latent image carrier to a recordingmedium; and fixing the toner image on the recording medium by heat,wherein the toner for developing electrostatic charge images accordingto claim 32 is used.
 34. The image forming method according to claim 33,wherein the transferring step comprises a first transferring step oftransferring the toner image on the electrostatic latent image carrierto an intermediate transfer medium and a second transferring step oftransferring the toner image on the intermediate transfer medium to therecording medium.
 35. An image forming apparatus comprising a chargingmeans of charging an electrostatic latent image carrier by applyingvoltage to a charging member from outside; an electrostatic charge imageforming means of forming an electrostatic charge image on the chargedelectrostatic latent image carrier; a developing means of developing theelectrostatic charge image with a toner for developing electrostaticcharge images to form a toner image on the electrostatic latent imagecarrier; a transferring means of transferring the toner image on theelectrostatic latent image carrier to a recording medium; and a fixingmeans of fixing the toner image on the recording medium by heat, whereinthe toner for developing electrostatic charge images according to claim32 is used.
 36. The image forming apparatus according to claim 35,wherein the transferring means comprises a first transferring means oftransferring the toner image on the electrostatic latent image carrierto an intermediate transfer medium and a second transferring means oftransferring the toner image on the intermediate transfer medium to therecording medium.